GAUSSLAT
The GAUSSLAT routine computes cosines of colatitude and Gaussian
weights on the Gaussian latitudes. The Gaussian latitudes
are at the zeroes of the legendre polynomial of the given order.
USAGE: CALL GAUSSLAT(JMAX,SLAT,WLAT)
Input argument list:
JMAX - INPUT NUMBER OF LATITUDES.
Output argument list:
SLAT - REAL (K) COSINES OF COLATITUDE.
WLAT - REAL (K) GAUSSIAN WEIGHTS.
GCDIST
The GCDIST function computes great circle distance
between two points on the earth.
USAGE: ...GCDIST(RLAT1,RLON1,RLAT2,RLON2)
Input argument list:
RLAT1 - REAL LATITUDE OF POINT 1 IN DEGREES
RLON1 - REAL LONGITUDE OF POINT 1 IN DEGREES
RLAT2 - REAL LATITUDE OF POINT 2 IN DEGREES
RLON2 - REAL LONGITUDE OF POINT 2 IN DEGREES
Output argument list:
GCDIST - REAL GREAT CIRCLE DISTANCE IN METERS
GDSAWT
The GDSAWT routine decodes the grib grid description section
and returns the earth's area covered by each grid point.
The grid and earth coordinates are also returned. The
edge points and corner points are given full weight now.
USAGE: CALL GDSAWT(KGDS,KB,KA,XPTS,YPTS,RLAT,RLON,AWT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
KB - INTEGER MAXIMUM NUMBER OF COORDINATES
Output argument list:
KA - INTEGER NUMBER OF VALID POINTS COMPUTED
XPTS - REAL (KB) GRID X POINT COORDINATES
YPTS - REAL (KB) GRID Y POINT COORDINATES
RLON - REAL (KB) EARTH LONGITUDES IN DEGREES
RLAT - REAL (KB) EARTH LATITUDES IN DEGREES N
AWT - REAL (KB) AREA WEIGHTS IN M**2
GDSWIZ
The GDSWIZ routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT= 0) grid and earth coordinates of all grid points
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
The current code recognizes the following projections:
(KGDS(1)=000) Equidistant cylindrical
(KGDS(1)=001) Mercator cylindrical
(KGDS(1)=003) Lambert conformal conical
(KGDS(1)=004) Gaussian cylindrical
(KGDS(1)=005) Polar stereographic azimuthaL
(KGDS(1)=201) Staggered rotated equidistant cylindrical
(KGDS(1)=202) Rotated equidistant cylindrical
(KGDS(1)=203) Staggered rotated equidistant cylindrical 2-D
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values. Also if iopt=0,
if the number of grid points exceeds the number allotted,
then all the output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
( 0 TO COMPUTE EARTH COORDS OF ALL THE GRID POINTS)
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<=0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<=0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>=0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>=0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
(-1 IF PROJECTION UNRECOGNIZED)
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZ00
The GDSWIZ00 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For equidistant cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ00(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZ01
The GDSWIZ01 decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Mercator cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ01(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZ03
The GDSWIZ03 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Lambert Conformal conical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ03(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZ04
The GDSWIZ04 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Gaussian cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ04(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZ05
The GDSWIZ05 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Polar Stereographic azimuthal projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZ05(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZC9
The GDSWIZC9 routine DECODES THE GRIB GRID DESCRIPTION SECTION
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Staggered rotated equidistant cylindrical projections.
(see under the description of kgds to determine whether
to compute a Staggered wind grid or a staggered mass grid.)
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZC9(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IMPORTANT NOTE: IF THE 9TH BIT (FROM RIGHT) OF KGDS(11)
(SCANNING MODE FLAG) IS 1, THEN THIS
THE GRID IS COMPUTED FOR A WIND FIELD;
OTHERWISE IT IS FOR A MASS FIELD. THUS
MOD(KGDS(11)/256,2)=0 FOR MASS GRID.
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZCA
The GDSWIZCA routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Rotated Equidistant cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZCA(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWIZCB
The GDSWIZCB routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Staggered rotated equidistant cylindrical projections.
(see under the description of kgds to determine whether
to compute a Staggered wind grid or a staggered mass grid.)
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
USAGE: CALL GDSWIZCB(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IMPORTANT NOTE: IF THE 9TH BIT (FROM RIGHT) OF KGDS(11)
(SCANNING MODE FLAG) IS 1, THEN THIS
THE GRID IS COMPUTED FOR A WIND FIELD;
OTHERWISE IT IS FOR A MASS FIELD. THUS
MOD(KGDS(11)/256,2)=0 FOR MASS GRID.
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
GDSWZD
The GDSWZD routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT= 0) grid and earth coordinates of all grid points
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=201) STAGGERED ROTATED EQUIDISTANT CYLINDRICAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL
(KGDS(1)=203) STAGGERED ROTATED EQUIDISTANT CYLINDRICAL 2-D
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values. Also if IOPT=0,
If the number of grid points exceeds the number allotted,
then all the output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZD(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
( 0 TO COMPUTE EARTH COORDS OF ALL THE GRID POINTS)
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<=0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<=0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>=0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>=0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
(-1 IF PROJECTION UNRECOGNIZED)
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
(PROPORTIONAL TO THE SQUARE OF THE MAP FACTOR
IN THE CASE OF CONFORMAL PROJECTIONS)
GDSWZD00
The GDSWZD00 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Equidistant cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZD00(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
INPUT ARGUMENT LIST:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
GDSWZD01
The GDSWZD01 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Mercator cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZD01(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
(PROPORTIONAL TO THE SQUARE OF THE MAP FACTOR)
GDSWZD03
The GDSWZD03 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Lambert Conformal conical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
optionally, the vector rotations and the map Jacobians
For this grid may be returned as well.
USAGE: CALL GDSWZD03(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
(PROPORTIONAL TO THE SQUARE OF THE MAP FACTOR)
GDSWZD04
The GDSWZD04 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Gaussian cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
the actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZD04(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
GDSWZD05
The GDSWZD05 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Polar Stereographic Azimuthal projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZD05(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
(PROPORTIONAL TO THE SQUARE OF THE MAP FACTOR)
GDSWZDC9
The GDSWZDC9 routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Staggered Rotated Equidistant cylindrical projections.
(See under the description of kgds to determine whether
to compute a Staggered wind grid or a Staggered mass grid.)
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZDC9(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IMPORTANT NOTE: IF THE 9TH BIT (FROM RIGHT) OF KGDS(11)
(SCANNING MODE FLAG) IS 1, THEN THIS
THE GRID IS COMPUTED FOR A WIND FIELD;
OTHERWISE IT IS FOR A MASS FIELD. THUS
MOD(KGDS(11)/256,2)=0 FOR MASS GRID.
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
GDSWZDCA
The GDSWZDCA routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Rotated Equidistant cylindrical projections.
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZDCA(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
GDSWZDCB
The GDSWZDCB routine decodes the grib grid description section
(passed in integer form as decoded by subprogram w3fi63)
and returns one of the following:
(IOPT=+1) earth coordinates of selected grid coordinates
(IOPT=-1) grid coordinates of selected earth coordinates
For Staggered Rotated Equidistant cylindrical projections.
(See under the description of kgds to determine whether
to compute a Staggered wind grid or a Staggered mass grid.)
If the selected coordinates are more than one gridpoint
beyond the the edges of the grid domain, then the relevant
output elements are set to fill values.
The actual number of valid points computed is returned too.
Optionally, the vector rotations and the map Jacobians
for this grid may be returned as well.
USAGE: CALL GDSWZDCB(KGDS,IOPT,NPTS,FILL,XPTS,YPTS,RLON,RLAT,NRET,
LROT,CROT,SROT,LMAP,XLON,XLAT,YLON,YLAT,AREA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
IMPORTANT NOTE: IF THE 9TH BIT (FROM RIGHT) OF KGDS(11)
(SCANNING MODE FLAG) IS 1, THEN THIS
THE GRID IS COMPUTED FOR A WIND FIELD;
OTHERWISE IT IS FOR A MASS FIELD. THUS
MOD(KGDS(11)/256,2)=0 FOR MASS GRID.
IOPT - INTEGER OPTION FLAG
(+1 TO COMPUTE EARTH COORDS OF SELECTED GRID COORDS)
(-1 TO COMPUTE GRID COORDS OF SELECTED EARTH COORDS)
NPTS - INTEGER MAXIMUM NUMBER OF COORDINATES
FILL - REAL FILL VALUE TO SET INVALID OUTPUT DATA
(MUST BE IMPOSSIBLE VALUE; SUGGESTED VALUE: -9999.)
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT>0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT>0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT<0
(ACCEPTABLE RANGE: -360. TO 360.)
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT<0
(ACCEPTABLE RANGE: -90. TO 90.)
LROT - INTEGER FLAG TO RETURN VECTOR ROTATIONS IF 1
LMAP - INTEGER FLAG TO RETURN MAP JACOBIANS IF 1
Output argument list:
XPTS - REAL (NPTS) GRID X POINT COORDINATES IF IOPT<0
YPTS - REAL (NPTS) GRID Y POINT COORDINATES IF IOPT<0
RLON - REAL (NPTS) EARTH LONGITUDES IN DEGREES E IF IOPT>0
RLAT - REAL (NPTS) EARTH LATITUDES IN DEGREES N IF IOPT>0
NRET - INTEGER NUMBER OF VALID POINTS COMPUTED
CROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION COSINES IF LROT=1
SROT - REAL (NPTS) CLOCKWISE VECTOR ROTATION SINES IF LROT=1
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
XLON - REAL (NPTS) DX/DLON IN 1/DEGREES IF LMAP=1
XLAT - REAL (NPTS) DX/DLAT IN 1/DEGREES IF LMAP=1
YLON - REAL (NPTS) DY/DLON IN 1/DEGREES IF LMAP=1
YLAT - REAL (NPTS) DY/DLAT IN 1/DEGREES IF LMAP=1
AREA - REAL (NPTS) AREA WEIGHTS IN M**2 IF LMAP=1
IJKGDS
The IJKGDS function decodes the grib grid description section
and returns the field position for a given grid point.
USAGE: ...IJKGDS(I,J,KGDS)
Input argument list:
I - INTEGER X GRID POINT
J - INTEGER Y GRID POINT
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
Output argument list:
IJKGDS - INTEGER POSITION IN GRIB FIELD TO LOCATE GRID POINT
(0 IF OUT OF BOUNDS)
IJKGDS0
The IJKGDS0 routine decodes the grib grid description section
and returns a navigation parameter array to allow function
IJKGDS1 to decode the field position for a given grid point.
USAGE: CALL IJKGDS0(KGDS,IJKGDSA)
Input argument list:
KGDS - INTEGER (200) GDS PARAMETERS AS DECODED BY W3FI63
Output argument list:
IJKGDSA - INTEGER (20) NAVIGATION PARAMETER ARRAY
IJKGDSA(1) IS NUMBER OF X POINTS
IJKGDSA(2) IS NUMBER OF Y POINTS
IJKGDSA(3) IS X WRAPAROUND INCREMENT
(0 IF NO WRAPAROUND)
IJKGDSA(4) IS Y WRAPAROUND LOWER PIVOT POINT
(0 IF NO WRAPAROUND)
IJKGDSA(5) IS Y WRAPAROUND UPPER PIVOT POINT
(0 IF NO WRAPAROUND)
IJKGDSA(6) IS SCANNING MODE
(0 IF X FIRST THEN Y; 1 IF Y FIRST THEN X;
2 IF STAGGERED DIAGONAL LIKE PROJECTION 201;
3 IF STAGGERED DIAGONAL LIKE PROJECTION 203)
IJKGDSA(7) IS MASS/WIND FLAG FOR STAGGERED DIAGONAL
(0 IF MASS; 1 IF WIND)
IJKGDSA(8:20) ARE UNUSED AT THE MOMENT
IJKGDS1
The IJKGDS1 function decodes the grib grid description section
and returns the field position for a given grid point.
call IJKGDS0 to set up the navigation parameter array.
USAGE: ...IJKGDS1(I,J,IJKGDSA)
Input argument list:
I - INTEGER X GRID POINT
J - INTEGER Y GRID POINT
IJKGDSA - INTEGER (20) NAVIGATION PARAMETER ARRAY
IJKGDSA(1) IS NUMBER OF X POINTS
IJKGDSA(2) IS NUMBER OF Y POINTS
IJKGDSA(3) IS X WRAPAROUND INCREMENT
(0 IF NO WRAPAROUND)
IJKGDSA(4) IS Y WRAPAROUND LOWER PIVOT POINT
(0 IF NO WRAPAROUND)
IJKGDSA(5) IS Y WRAPAROUND UPPER PIVOT POINT
(0 IF NO WRAPAROUND)
IJKGDSA(6) IS SCANNING MODE
(0 IF X FIRST THEN Y; 1 IF Y FIRST THEN X;
2 IF STAGGERED DIAGONAL LIKE PROJECTION 201;
3 IF STAGGERED DIAGONAL LIKE PROJECTION 203)
IJKGDSA(7) IS MASS/WIND FLAG FOR STAGGERED DIAGONAL
(0 IF MASS; 1 IF WIND)
IJKGDSA(8:20) ARE UNUSED AT THE MOMENT
Output argument list:
IJKGDS - INTEGER POSITION IN GRIB FIELD TO LOCATE GRID POINT
(0 IF OUT OF BOUNDS)
IPMERGE2
The IPMERGE2 routine merges two bitmapped fields into one.
where both input fields are valid, the first field is taken.
where neither input field is valid, the output is invalid.
USAGE: CALL IPMERGE2(NO,NF,M1,L1,F1,M2,L2,F2,MO,LO,FO)
Input argument list:
NO - INTEGER NUMBER OF POINTS IN EACH FIELD
NF - INTEGER NUMBER OF FIELDS MERGES
M1 - INTEGER FIRST DIMENSION OF FIELD 1 ARRAYS
L1 - LOGICAL(1) (M1,NF) BITMAP FOR FIELD 1
F1 - REAL (M1,NF) DATA FOR FIELD 1
M2 - INTEGER FIRST DIMENSION OF FIELD 2 ARRAYS
L2 - LOGICAL(1) (M2,NF) BITMAP FOR FIELD 2
F2 - REAL (M2,NF) DATA FOR FIELD 2
MO - INTEGER FIRST DIMENSION OF OUTPUT FIELD ARRAYS
Output argument list:
LO - LOGICAL(1) (MO,NF) BITMAP FOR OUTPUT FIELD
FO - REAL (MO,NF) DATA FOR OUTPUT FIELD
IPOLATES
The IPOLATES routine interpolates scalar fields
from any grid to any grid. Only horizontal
interpolation is performed.
The following interpolation methods are possible:
(IP=0) BILINEAR
(IP=1) BICUBIC
(IP=2) NEIGHBOR
(IP=3) BUDGET
(IP=4) SPECTRAL
(IP=6) NEIGHBOR-BUDGET
Some of these methods have interpolation options and/or
restrictions on the input or output grids, both of which
are documented more fully in their respective subprograms.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=201) ROTATED EQUIDISTANT CYLINDRICAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
input bitmaps will be interpolated to output bitmaps.
output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL IPOLATES(IP,IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IP - INTEGER INTERPOLATION METHOD
(IP=0 FOR BILINEAR;
IP=1 FOR BICUBIC;
IP=2 FOR NEIGHBOR;
IP=3 FOR BUDGET;
IP=4 FOR SPECTRAL;
IP=6 FOR NEIGHBOR-BUDGET)
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
(IP=0: (NO OPTIONS)
IP=1: CONSTRAINT OPTION
IP=2: (NO OPTIONS)
IP=3: NUMBER IN RADIUS, RADIUS WEIGHTS ...
IP=4: SPECTRAL SHAPE, SPECTRAL TRUNCATION
IP=6: NUMBER IN RADIUS, RADIUS WEIGHTS ...)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF RESPECTIVE IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
1 UNRECOGNIZED INTERPOLATION METHOD
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
1X INVALID BICUBIC METHOD PARAMETERS
3X INVALID BUDGET METHOD PARAMETERS
4X INVALID SPECTRAL METHOD PARAMETERS
IPOLATEV
The IPOLATEV routine interpolates vector fields
from any grid to any grid. Only horizontal
interpolation is performed.
The following interpolation methods are possible:
(IP=0) BILINEAR
(IP=1) BICUBIC
(IP=2) NEIGHBOR
(IP=3) BUDGET
(IP=4) SPECTRAL
(IP=6) NEIGHBOR-BUDGET
Some of these methods have interpolation options and/or
restrictions on the input or output grids, both of which
are documented more fully in their respective subprograms.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=201) ROTATED EQUIDISTANT CYLINDRICAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
input bitmaps will be interpolated to output bitmaps.
output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL IPOLATEV(IP,IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IP - INTEGER INTERPOLATION METHOD
(IP=0 FOR BILINEAR;
IP=1 FOR BICUBIC;
IP=2 FOR NEIGHBOR;
IP=3 FOR BUDGET;
IP=4 FOR SPECTRAL;
IP=6 FOR NEIGHBOR-BUDGET)
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
(IP=0: (NO OPTIONS)
IP=1: CONSTRAINT OPTION
IP=2: (NO OPTIONS)
IP=3: NUMBER IN RADIUS, RADIUS WEIGHTS ...
IP=4: SPECTRAL SHAPE, SPECTRAL TRUNCATION
IP=6: NUMBER IN RADIUS, RADIUS WEIGHTS ...)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
NOTE: IF KGDSI(201)=1 THEN THE 9TH BIT OF KGDSI(11)
IS TEMPORARILY SET TO 1 TO ALERT THE GDS WIZARD
THAT THESE FIELDS ARE STAGGERED ETA WINDS.
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
NOTE: IF KGDSO(201)=1 THEN THE 9TH BIT OF KGDSO(11)
IS TEMPORARILY SET TO 1 TO ALERT THE GDS WIZARD
THAT THESE FIELDS ARE STAGGERED ETA WINDS.
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF RESPECTIVE IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
CROT - REAL (MO) VECTOR ROTATION COSINES (IF KGDSO(1)>=0)
SROT - REAL (MO) VECTOR ROTATION SINES (IF KGDSO(1)>=0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
1 UNRECOGNIZED INTERPOLATION METHOD
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
1X INVALID BICUBIC METHOD PARAMETERS
3X INVALID BUDGET METHOD PARAMETERS
4X INVALID SPECTRAL METHOD PARAMETERS
REMARKS:
EXAMPLES DEMONSTRATING RELATIVE CPU COSTS.
THIS EXAMPLE IS INTERPOLATING 12 LEVELS OF WINDS
FROM THE 360 X 181 GLOBAL GRID (NCEP GRID 3)
TO THE 93 X 68 HAWAIIAN MERCATOR GRID (NCEP GRID 204).
THE EXAMPLE TIMES ARE FOR THE C90. AS A REFERENCE, THE CP TIME
FOR UNPACKING THE GLOBAL 12 PAIRS OF WIND FIELDS IS 0.07 SECONDS.
BILINEAR 0 0.05
BICUBIC 1 0 0.16
BICUBIC 1 1 0.17
NEIGHBOR 2 0.02
BUDGET 3 -1,-1 0.94
SPECTRAL 4 0,40 0.31
SPECTRAL 4 1,40 0.33
SPECTRAL 4 0,-1 0.59
N-BUDGET 6 0,-1 0.31
THE SPECTRAL INTERPOLATION IS FAST FOR THE MERCATOR GRID.
HOWEVER, FOR SOME GRIDS THE SPECTRAL INTERPOLATION IS SLOW.
THE FOLLOWING EXAMPLE IS INTERPOLATING 12 LEVELS OF WINDS
FROM THE 360 X 181 GLOBAL GRID (NCEP GRID 3)
TO THE 93 X 65 CONUS LAMBERT CONFORMAL GRID (NCEP GRID 211).
IPSECTOR
The IPSECTOR routine creates a subsector of a grid,
computing a new grid definition section and copying data
from the original grid data.
USAGE: CALL IPSECTOR(I1,I2,J1,J2,NF,M,KGDS,L,F,MS,
KGDSS,LS,FS,IRET)
Input argument list:
I1 - INTEGER FIRST X POINT OF THE SECTOR
OR IF 0<=I2IPSPASTE
The IPSPASTE routine pastes a subsector of a grid back
into the original grid.
USAGE: CALL IPSPASTE(I1,I2,J1,J2,NF,MS,LS,FS,M,KGDS,L,F,IRET)
Input argument list:
I1 - INTEGER FIRST X POINT OF THE SECTOR
OR IF 0<=I2IPXETAS
The IPXETAS routine transforms between the staggered eta grids
as used in the eta model and for native grid transmission
and their full expansion as used for general interpolation
and graphics. The eta grids are rotated latitude-longitude
grids staggered as defined by the Arakawa e-grid, that is
with mass data points alternating with wind data points.
The expansion of the fields is done by 4-point averaging.
USAGE: CALL IPXETAS(IDIR,M1,M2,KM,KGDS1,F1,KGDS2,F2,IRET)
Input argument list:
IDIR - INTEGER TRANSFORM OPTION
(+1 TO EXPAND STAGGERED MASS FIELDS TO FULL FIELDS)
(+2 TO EXPAND STAGGERED WIND FIELDS TO FULL FIELDS)
(-1 TO CONTRACT FULL MASS FIELDS TO STAGGERED FIELDS)
(-2 TO CONTRACT FULL WIND FIELDS TO STAGGERED FIELDS)
M1 - INTEGER SKIP NUMBER BETWEEN STAGGERED GRID FIELDS
M2 - INTEGER SKIP NUMBER BETWEEN FULL GRID FIELDS
KM - INTEGER NUMBER OF FIELDS TO TRANSFORM
KGDS1 - INTEGER (200) GDS PARMS OF STAGGERED GRID IF IDIR>0
F1 - REAL (M1,KM) STAGGERED GRID FIELDS IF IDIR>0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR<0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR<0
Output argument list:
KGDS1 - INTEGER (200) GDS PARMS OF STAGGERED GRID IF IDIR<0
F1 - REAL (M1,KM) STAGGERED GRID FIELDS IF IDIR<0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR>0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR>0
IRET - INTEGER RETURN CODE
0 SUCCESSFUL TRANSFORMATION
1 IMPROPER GRID SPECIFICATION
IPXWAFS
The IPXWAFS routine transforms between the thinned WAFS grids
as used for transmitting to the aviation community
and their full expansion as used for general interpolation
and graphics. The WAFS grids are latitude-longitude grids
thinned only in the zonal direction as indicated
By the PL parameters in the grib grid description section.
The PL parameters must be supplied for contraction
(starting at KGDS1(22)). Otherwise (If KGDS1(22)<=0)
grid contraction is performed specifically for
The 1.25 degree NCEP WAFS grid identifications 37-44.
The expansion and contraction of the fields are done
by linear interpolation, so that they are not reversible.
USAGE: CALL IPXWAFS(IDIR,M1,M2,KM,KGDS1,F1,KGDS2,F2,IRET)
Input argument list:
IDIR - INTEGER TRANSFORM OPTION
(+1 TO EXPAND THINNED FIELDS TO FULL FIELDS)
(-1 TO CONTRACT FULL FIELDS TO THINNED FIELDS)
M1 - INTEGER SKIP NUMBER BETWEEN THINNED GRID FIELDS
M2 - INTEGER SKIP NUMBER BETWEEN FULL GRID FIELDS
KM - INTEGER NUMBER OF FIELDS TO TRANSFORM
KGDS1 - INTEGER (200) GDS PARMS OF THINNED GRID IF IDIR>0
(IF IDIR<0, THEN EITHER THE PL PARAMETERS STARTING AT
KGDS1(22) MUST BE SUPPLIED OR IF KGDS1(22)<=0,
THEN THE PL PARAMETERS DEFAULT TO THOSE FOR
SPECIFIC NCEP WAFS GRIDS 37-44).
F1 - REAL (M1,KM) THINNED GRID FIELDS IF IDIR>0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR<0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR<0
Output argument list:
KGDS1 - INTEGER (200) GDS PARMS OF THINNED GRID IF IDIR<0
F1 - REAL (M1,KM) THINNED GRID FIELDS IF IDIR<0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR>0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR>0
IRET - INTEGER RETURN CODE
0 SUCCESSFUL TRANSFORMATION
1 IMPROPER GRID SPECIFICATION
IPXWAFS2
The IPXWAFS2 routine transforms between the thinned wafs grids
as used for transmitting to the aviation community
and their full expansion as used for general interpolation
and graphics. The WAFS grids are latitude-longitude grids
thinned only in the zonal direction as indicated
by the PL parameters in the grib grid description section.
The PL parameters must be supplied for contraction
(starting at KGDS1(22)). Otherwise (if KGDS1(22)<=0)
grid contraction is performed specifically for
The 1.25 degree NCEP WAFS grid identifications 37-44.
The expansion and contraction of the fields are done
by linear interpolation, so that they are not reversible.
This version allows a bitmap.
USAGE: CALL IPXWAFS2(IDIR,M1,M2,KM,
KGDS1,IB1,L1,F1,KGDS2,IB2,L2,F2,IRET)
Input argument list:
IDIR - INTEGER TRANSFORM OPTION
(+1 TO EXPAND THINNED FIELDS TO FULL FIELDS)
(-1 TO CONTRACT FULL FIELDS TO THINNED FIELDS)
M1 - INTEGER SKIP NUMBER BETWEEN THINNED GRID FIELDS
M2 - INTEGER SKIP NUMBER BETWEEN FULL GRID FIELDS
KM - INTEGER NUMBER OF FIELDS TO TRANSFORM
KGDS1 - INTEGER (200) GDS PARMS OF THINNED GRID IF IDIR>0
(IF IDIR<0, THEN EITHER THE PL PARAMETERS STARTING AT
KGDS1(22) MUST BE SUPPLIED OR IF KGDS1(22)<=0,
THEN THE PL PARAMETERS DEFAULT TO THOSE FOR
SPECIFIC NCEP WAFS GRIDS 37-44).
IB1 - INTEGER (KM) THINNED BITMAP FLAGS IF IDIR>0
L1 - LOGICAL*1 (M1,KM) THINNED BITMAP FIELDS IF IDIR>0
F1 - REAL (M1,KM) THINNED GRID FIELDS IF IDIR>0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR<0
IB2 - INTEGER (KM) FULL BITMAP FLAGS IF IDIR<0
L2 - LOGICAL*1 (M1,KM) FULL BITMAP FIELDS IF IDIR<0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR<0
Output argument list:
KGDS1 - INTEGER (200) GDS PARMS OF THINNED GRID IF IDIR<0
IB1 - INTEGER (KM) THINNED BITMAP FLAGS IF IDIR<0
L1 - LOGICAL*1 (M1,KM) THINNED BITMAP FIELDS IF IDIR<0
F1 - REAL (M1,KM) THINNED GRID FIELDS IF IDIR<0
KGDS2 - INTEGER (200) GDS PARMS OF FULL GRID IF IDIR>0
IB2 - INTEGER (KM) FULL BITMAP FLAGS IF IDIR>0
L2 - LOGICAL*1 (M1,KM) FULL BITMAP FIELDS IF IDIR>0
F2 - REAL (M2,KM) FULL GRID FIELDS IF IDIR>0
IRET - INTEGER RETURN CODE
0 SUCCESSFUL TRANSFORMATION
1 IMPROPER GRID SPECIFICATION
MAKGDS
The MAKGDS routine makes or breaks a grid description section.
It can do one of the following:
(IOPT=-1) unpack a GDS into w3fi63 kgds integer form
(IOPT=255) pack a GDS from W3FI63 KGDS integer form
(IOPT<255) pack a GDS from an NCEP grid identification.
USAGE: CALL MAKGDS(IOPT,KGDS,GDS,LENGDS,IRET)
Input argument list:
IOPT - INTEGER OPTION
IOPT=-1 TO UNPACK GDS INTO KGDS;
IOPT=255 TO USE KGDS TO PACK GDS;
IOPT<255 NCEP GRID ID TO MAKE GDS AND KGDS.
KGDS - INTEGER (200) W3FI63-STYLE UNPACKED GDS (IF IOPT=255)
(ONLY FIRST 22 VALUES ARE ACCESSED IF KGDS(20)=255.)
(SEE REMARKS BELOW FOR A DETAILED DESCRIPTION OF KGDS.)
GDS - CHARACTER (400) GRID DEFINITION SECTION (IF IOPT=-1)
Output argument list:
KGDS - INTEGER (200) W3FI63-STYLE UNPACKED GDS (IF IOPT<255)
(ONLY FIRST 22 VALUES ARE ACCESSED IF KGDS(20)=255.)
(SEE REMARKS BELOW FOR A DETAILED DESCRIPTION OF KGDS.)
GDS - CHARACTER (400) GRID DEFINITION SECTION (IF IOPT>0)
LENGDS - INTEGER LENGTH OF THE GDS (IF IOPT>0)
IRET - INTEGER RETURN CODE
0 SUCCESSFUL
1 GRID REPRESENTATION TYPE NOT VALID
4 DATA REPRESENTATION TYPE NOT CURRENTLY ACCEPTABLE
REMARKS:
THE KGDS PARAMETERS ARE DESCRIBED BELOW
AS COPIED FROM THE W3FI63 DOCBLOCK.
(1) - DATA REPRESENTATION TYPE
(19) - NUMBER OF VERTICAL COORDINATE PARAMETERS
(20) - OCTET NUMBER OF THE LIST OF VERTICAL COORDINATE
PARAMETERS
OR
OCTET NUMBER OF THE LIST OF NUMBERS OF POINTS
IN EACH ROW
OR
255 IF NEITHER ARE PRESENT
(21) - FOR GRIDS WITH PL, NUMBER OF POINTS IN GRID
(22) - NUMBER OF WORDS IN EACH ROW
LATITUDE/LONGITUDE GRIDS
(2) - N(I) NR POINTS ON LATITUDE CIRCLE
(3) - N(J) NR POINTS ON LONGITUDE MERIDIAN
(4) - LA(1) LATITUDE OF ORIGIN
(5) - LO(1) LONGITUDE OF ORIGIN
(6) - RESOLUTION FLAG (RIGHT ADJ COPY OF OCTET 17)
(7) - LA(2) LATITUDE OF EXTREME POINT
(8) - LO(2) LONGITUDE OF EXTREME POINT
(9) - DI LATITUDINAL DIRECTION OF INCREMENT
(10) - DJ LONGITUDINAL DIRECTION INCREMENT
(11) - SCANNING MODE FLAG (RIGHT ADJ COPY OF OCTET 28)
GAUSSIAN GRIDS
(2) - N(I) NR POINTS ON LATITUDE CIRCLE
(3) - N(J) NR POINTS ON LONGITUDE MERIDIAN
(4) - LA(1) LATITUDE OF ORIGIN
(5) - LO(1) LONGITUDE OF ORIGIN
(6) - RESOLUTION FLAG (RIGHT ADJ COPY OF OCTET 17)
(7) - LA(2) LATITUDE OF EXTREME POINT
(8) - LO(2) LONGITUDE OF EXTREME POINT
(9) - DI LATITUDINAL DIRECTION OF INCREMENT
(10) - N - NR OF CIRCLES POLE TO EQUATOR
(11) - SCANNING MODE FLAG (RIGHT ADJ COPY OF OCTET 28)
(12) - NV - NR OF VERT COORD PARAMETERS
(13) - PV - OCTET NR OF LIST OF VERT COORD PARAMETERS
OR
PL - LOCATION OF THE LIST OF NUMBERS OF POINTS IN
EACH ROW (IF NO VERT COORD PARAMETERS
ARE PRESENT
OR
255 IF NEITHER ARE PRESENT
POLAR STEREOGRAPHIC GRIDS
(2) - N(I) NR POINTS ALONG LAT CIRCLE
(3) - N(J) NR POINTS ALONG LON CIRCLE
(4) - LA(1) LATITUDE OF ORIGIN
(5) - LO(1) LONGITUDE OF ORIGIN
(6) - RESOLUTION FLAG (RIGHT ADJ COPY OF OCTET 17)
(7) - LOV GRID ORIENTATION
(8) - DX - X DIRECTION INCREMENT
(9) - DY - Y DIRECTION INCREMENT
(10) - PROJECTION CENTER FLAG
(11) - SCANNING MODE (RIGHT ADJ COPY OF OCTET 28)
SPHERICAL HARMONIC COEFFICIENTS
(2) - J PENTAGONAL RESOLUTION PARAMETER
(3) - K " " "
(4) - M " " "
(5) - REPRESENTATION TYPE
(6) - COEFFICIENT STORAGE MODE
MERCATOR GRIDS
(2) - N(I) NR POINTS ON LATITUDE CIRCLE
(3) - N(J) NR POINTS ON LONGITUDE MERIDIAN
(4) - LA(1) LATITUDE OF ORIGIN
(5) - LO(1) LONGITUDE OF ORIGIN
(6) - RESOLUTION FLAG (RIGHT ADJ COPY OF OCTET 17)
(7) - LA(2) LATITUDE OF LAST GRID POINT
(8) - LO(2) LONGITUDE OF LAST GRID POINT
(9) - LATIT - LATITUDE OF PROJECTION INTERSECTION
(10) - RESERVED
(11) - SCANNING MODE FLAG (RIGHT ADJ COPY OF OCTET 28)
(12) - LONGITUDINAL DIR GRID LENGTH
(13) - LATITUDINAL DIR GRID LENGTH
LAMBERT CONFORMAL GRIDS
(2) - NX NR POINTS ALONG X-AXIS
(3) - NY NR POINTS ALONG Y-AXIS
(4) - LA1 LAT OF ORIGIN (LOWER LEFT)
(5) - LO1 LON OF ORIGIN (LOWER LEFT)
(6) - RESOLUTION (RIGHT ADJ COPY OF OCTET 17)
(7) - LOV - ORIENTATION OF GRID
(8) - DX - X-DIR INCREMENT
(9) - DY - Y-DIR INCREMENT
(10) - PROJECTION CENTER FLAG
(11) - SCANNING MODE FLAG (RIGHT ADJ COPY OF OCTET 28)
(12) - LATIN 1 - FIRST LAT FROM POLE OF SECANT CONE INTER
(13) - LATIN 2 - SECOND LAT FROM POLE OF SECANT CONE INTER
MOVECT
The MOVECT routine provides the rotation parameters
to move a vector along a great circle from one
position to another while conserving its orientation
with respect to the great circle. These rotation
parameters are useful for vector interpolation.
USAGE: CALL MOVECT(FLAT,FLON,TLAT,TLON,CROT,SROT)
Input argument list:
FLAT - REAL LATITUDE IN DEGREES FROM WHICH TO MOVE THE VECTOR
FLON - REAL LONGITUDE IN DEGREES FROM WHICH TO MOVE THE VECTOR
TLAT - REAL LATITUDE IN DEGREES TO WHICH TO MOVE THE VECTOR
TLON - REAL LONGITUDE IN DEGREES TO WHICH TO MOVE THE VECTOR
Output argument list:
CROT - REAL CLOCKWISE VECTOR ROTATION COSINE
SROT - REAL CLOCKWISE VECTOR ROTATION SINE
(UTO=CROT*UFROM-SROT*VFROM;
VTO=SROT*UFROM+CROT*VFROM)
REMARKS:
THIS SUBPROGRAM IS CORRECT TO SEVEN DIGITS ON THE CRAYS.
USE DOUBLE PRECISION IF BETTER PRECISION IS REQUIRED.
POLATEG0
The POLATEG0 routine performs bilinear interpolation
from any grid to any grid for scalar fields,
returning their vector gradients. No options are
allowed. Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEG0(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,XO,YO,IRET)
INPUT ARGUMENT LIST:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS (NO OPTIONS)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
OUTPUT ARGUMENT LIST:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
XO - REAL (MO,KM) OUTPUT X-GRADIENT FIELDS INTERPOLATED
YO - REAL (MO,KM) OUTPUT Y-GRADIENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
REMARKS:
THE GRADIENT COMPUTATIONS ARE NOT ROBUST NEAR THE POLES.
IN FACT, NO GRADIENTS ARE COMPUTED POLEWARD OF 89 LATITUDE.
POLATEG1
The POLATEG1 routine performs bicubic interpolation
from any grid to any grid for scalar fields,
returning their vector gradients. Bitmaps are now
allowed, but bilinear interpolation is done when any
invalid data is within the bicubic template.
options allow choices between Straight Bicubic (ipopt(1)=0)
and Constrained Bicubic (ipopt(1)=1) where the value is
confined within the range of the surrounding 4 points.
bilinear used within one grid length of boundaries.
only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEG1(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,XO,YO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR STRAIGHT BICUBIC;
IPOPT(1)=1 FOR CONSTRAINED BICUBIC WHERE VALUE IS
CONFINED WITHIN THE RANGE OF THE SURROUNDING 4 POINTS.
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS (MUST BE ALL 0)
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
XO - REAL (MO,KM) OUTPUT X-GRADIENT FIELDS INTERPOLATED
YO - REAL (MO,KM) OUTPUT Y-GRADIENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATEG4
The POLATEG4 routine PERFORMS SPECTRAL INTERPOLATION
from any grid to any grid for scalar fields,
returning their vector gradients. It requires
that the input fields be uniformly global.
Options allow choices between triangular shape (IPOPT(1)=0)
and rhomboidal shape (IPOPT(1)=1) which has no default;
A second option is the truncation (IPOPT(2)) which defaults
To a sensible truncation for the input grid (if OPT(2)=-1).
Note that if the output grid is not found in a special list,
then the transform back to grid is not very fast.
This special list contains global cylindrical grids,
Polar Stereographic grids centered at the pole and Mercator
grids. Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Output bitmaps will not be created.
USAGE: CALL POLATEG4(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR TRIANGULAR, IPOPT(1)=1 FOR RHOMBOIDAL;
IPOPT(2) IS TRUNCATION NUMBER
(DEFAULTS TO SENSIBLE IF IPOPT(2)=-1).
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS (MUST BE ALL 0)
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
41 INVALID NONGLOBAL INPUT GRID
42 INVALID SPECTRAL METHOD PARAMETERS
43 UNIMPLEMENTED OUTPUT GRID
POLATES0
The POLATES0 routine performs bilinear interpolation
from any grid to any grid for scalar fields.
options allow varying the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(1)) which defaults to 50 (if ipopt(1)=-1).
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATES0(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATES1
The POLATES1 routine performs bicubic interpolation
from any grid to any grid for scalar fields.
bitmaps are now allowed, but bilinear interpolation is done
when any invalid data is within the bicubic template.
Options allow choices between straight bicubic (ipopt(1)=0)
and constrained bicubic (ipopt(1)=1) where the value is
confined within the range of the surrounding 4 points.
Another option is the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(2)) which defaults to 50 (if ipopt(2)=-1).
Bilinear used within one grid length of boundaries.
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATES1(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR STRAIGHT BICUBIC;
IPOPT(1)=1 FOR CONSTRAINED BICUBIC WHERE VALUE IS
CONFINED WITHIN THE RANGE OF THE SURROUNDING 4 POINTS.
IPOPT(2) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(2)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATES2
The POLATES2 routine performs neighbor interpolation
from any grid to any grid for scalar fields.
options allow choosing the width of the grid square
(ipopt(1)) to search for valid data, which defaults to 1
(if ipopt(1)=-1). Odd width squares are centered on
the nearest input grid point; Even width squares are
centered on the nearest four input grid points.
Squares are searched for valid data in a spiral pattern
starting from the center. No searching is done where
the output grid is outside the input grid.
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATES2(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS WIDTH OF SQUARE TO EXAMINE IN SPIRAL SEARCH
(DEFAULTS TO 1 IF IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATES3
The POLATES3 routine PERFORMS BUDGET INTERPOLATION
FROM ANY GRID TO ANY GRID FOR SCALAR FIELDS.
IT REQUIRES A GRID FOR THE OUTPUT FIELDS (KGDSO(1)>=0).
THE ALGORITHM SIMPLY COMPUTES (WEIGHTED) AVERAGES
OF BILINEARLY INTERPOLATED POINTS ARRANGED IN A SQUARE BOX
CENTERED AROUND EACH OUTPUT GRID POINT AND STRETCHING
NEARLY HALFWAY TO EACH OF THE NEIGHBORING GRID POINTS.
OPTIONS ALLOW CHOICES OF NUMBER OF POINTS IN EACH RADIUS
FROM THE CENTER POINT (IPOPT(1)) WHICH DEFAULTS TO 2
(IF IPOPT(1)=-1) MEANING THAT 25 POINTS WILL BE AVERAGED;
FURTHER OPTIONS ARE THE RESPECTIVE WEIGHTS FOR THE RADIUS
POINTS STARTING AT THE CENTER POINT (IPOPT(2:2+IPOPT(1))
WHICH DEFAULTS TO ALL 1 (IF IPOPT(1)=-1 OR IPOPT(2)=-1).
A SPECIAL INTERPOLATION IS DONE IF IPOPT(2)=-2.
IN THIS CASE, THE BOXES STRETCH NEARLY ALL THE WAY TO
EACH OF THE NEIGHBORING GRID POINTS AND THE WEIGHTS
ARE THE ADJOINT OF THE BILINEAR INTERPOLATION WEIGHTS.
THIS CASE GIVES QUASI-SECOND-ORDER BUDGET INTERPOLATION.
ANOTHER OPTION IS THE MINIMUM PERCENTAGE FOR MASK,
I.E. PERCENT VALID INPUT DATA REQUIRED TO MAKE OUTPUT DATA,
(IPOPT(3+IPOPT(1)) WHICH DEFAULTS TO 50 (IF -1).
ONLY HORIZONTAL INTERPOLATION IS PERFORMED.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATES3(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS NUMBER OF RADIUS POINTS
(DEFAULTS TO 2 IF IPOPT(1)=-1);
IPOPT(2:2+IPOPT(1)) ARE RESPECTIVE WEIGHTS
(DEFAULTS TO ALL 1 IF IPOPT(1)=-1 OR IPOPT(2)=-1).
IPOPT(3+IPOPT(1)) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(3+IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
31 INVALID UNDEFINED OUTPUT GRID
32 INVALID BUDGET METHOD PARAMETERS
POLATES4
The POLATES4 routine performs spectral interpolation
from any grid to any grid for scalar fields.
It requires that the input fields be uniformly global.
Options allow choices between triangular shape (ipopt(1)=0)
and rhomboidal shape (ipopt(1)=1) which has no default;
A second option is the truncation (ipopt(2)) which defaults
to a sensible truncation for the input grid (if opt(2)=-1).
Note that if the output grid is not found in a special list,
then the transform back to grid is not very fast.
This special list contains global cylindrical grids,
Polar Stereographic grids centered at the pole and
Mercator grids.
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Output bitmaps will not be created.
USAGE: CALL POLATES4(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR TRIANGULAR, IPOPT(1)=1 FOR RHOMBOIDAL;
IPOPT(2) IS TRUNCATION NUMBER
(DEFAULTS TO SENSIBLE IF IPOPT(2)=-1).
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS (MUST BE ALL 0)
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
41 INVALID NONGLOBAL INPUT GRID
42 INVALID SPECTRAL METHOD PARAMETERS
POLATES6
The POLATES6 routine performs budget interpolation
from any grid to any grid for scalar fields.
It requires a grid for the output fields (kgdso(1)>=0).
The algorithm simply computes (weighted) averages
of neighbor points arranged in a square box
centered around each output grid point and stretching
nearly halfway to each of the neighboring grid points.
Options allow choices of number of points in each radius
from the center point (ipopt(1)) which defaults to 2
(if ipopt(1)=-1) meaning that 25 points will be averaged;
Further options are the respective weights for the radius
points starting at the center point (ipopt(2:2+ipopt(1))
which defaults to all 1 (if ipopt(1)=-1 or ipopt(2)=-1).
another option is the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(3+ipopt(1)) which defaults to 50 (if -1).
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
Input bitmaps will be interpolated to output bitmaps.
output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
the output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATES6(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,GI,
NO,RLAT,RLON,IBO,LO,GO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS NUMBER OF RADIUS POINTS
(DEFAULTS TO 2 IF IPOPT(1)=-1);
IPOPT(2:2+IPOPT(1)) ARE RESPECTIVE WEIGHTS
(DEFAULTS TO ALL 1 IF IPOPT(1)=-1 OR IPOPT(2)=-1).
IPOPT(3+IPOPT(1)) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(3+IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
GI - REAL (MI,KM) INPUT FIELDS TO INTERPOLATE
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
GO - REAL (MO,KM) OUTPUT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
31 INVALID UNDEFINED OUTPUT GRID
32 INVALID BUDGET METHOD PARAMETERS
POLATEV0
The POLATEV0 routine performs bilinear interpolation
from any grid to any grid for vector fields.
options allow varying the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(1)) which defaults to 50 (if ipopt(1)=-1).
only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
Along with their vector rotation parameters.
On the other hand, the output can be a set of station points
If kgdso(1)<0, in which case the number of points
and their latitudes and longitudes must be input
Along with their vector rotation parameters.
Input bitmaps will be interpolated to output bitmaps.
output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV0(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)>=0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)>=0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATEV1
The POLATEV1 routine performs bicubic interpolation
from any grid to any grid for scalar fields.
Bitmaps are now allowed, but bilinear interpolation is done
when any invalid data is within the bicubic template.
Options allow choices between straight bicubic (ipopt(1)=0)
and constrained bicubic (ipopt(1)=1) where the value is
confined within the range of the surrounding 4 points.
Another option is the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(2)) which defaults to 50 (if ipopt(2)=-1).
Bilinear used within one grid length of boundaries.
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
Along with their vector rotation parameters.
On the other hand, the output can be a set of station points
If kgdso(1)<0, in which case the number of points
and their latitudes and longitudes must be input
along with their vector rotation parameters.
Output bitmaps will only be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV1(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR STRAIGHT BICUBIC;
IPOPT(1)=1 FOR CONSTRAINED BICUBIC WHERE VALUE IS
CONFINED WITHIN THE RANGE OF THE SURROUNDING 4 POINTS.
IPOPT(2) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(2)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)>=0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)>=0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATEV2
The POLATEV2 routine performs neighbor interpolation
from any grid to any grid for vector fields.
Options allow choosing the width of the grid square
(ipopt(1)) to search for valid data, which defaults to 1
(if ipopt(1)=-1). Odd width squares are centered on
the nearest input grid point; Even width squares are
centered on the nearest four input grid points.
Squares are searched for valid data in a spiral pattern
starting from the center. No searching is done where
the output grid is outside the input grid. Only horizontal
interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned.
Along with their vector rotation parameters.
On the other hand, the output can be a set of station points
If KGDSO(1)<0, in which case the number of points
and their latitudes and longitudes must be input.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV2(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS WIDTH OF SQUARE TO EXAMINE IN SPIRAL SEARCH
(DEFAULTS TO 1 IF IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)>=0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)>=0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
POLATEV3
The POLATEV3 routine performs budget interpolation
from any grid to any grid for vector fields.
It requires a grid for the output fields (kgdso(1)>=0).
The algorithm simply computes (weighted) averages
of Bilinearly interpolated points arranged in a square box
centered around each output grid point and stretching
nearly halfway to each of the neighboring grid points.
Options allow choices of number of points in each radius
from the center point (ipopt(1)) which defaults to 2
(if ipopt(1)=-1) meaning that 25 points will be averaged;
Further options are the respective weights for the radius
points starting at the center point (ipopt(2:2+ipopt(1))
which defaults to all 1 (if ipopt(1)=-1 or ipopt(2)=-1).
A special interpolation is done if ipopt(2)=-2.
In this case, the boxes stretch nearly all the way to
each of the neighboring grid points and the weights
are the adjoint of the Bilinear interpolation weights.
This case gives Quasi-Second-Order Budget interpolation.
Another option is the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(3+ipopt(1)) which defaults to 50 (if -1).
Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
The input and output vectors are rotated so that they are
either resolved relative to the defined grid
in the direction of increasing x and y coordinates
or resolved relative to easterly and northerly directions,
as designated by their respective grid description sections.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned
Along with their vector rotation parameters.
Input bitmaps will be interpolated to output bitmaps.
Output bitmaps will also be created when the output grid
Extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV3(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS NUMBER OF RADIUS POINTS
(DEFAULTS TO 2 IF IPOPT(1)=-1);
IPOPT(2:2+IPOPT(1)) ARE RESPECTIVE WEIGHTS
(DEFAULTS TO ALL 1 IF IPOPT(1)=-1 OR IPOPT(2)=-1).
IPOPT(3+IPOPT(1)) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(3+IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES
CROT - REAL (NO) VECTOR ROTATION COSINES
SROT - REAL (NO) VECTOR ROTATION SINES
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
31 INVALID UNDEFINED OUTPUT GRID
32 INVALID BUDGET METHOD PARAMETERS
POLATEV4
The POLATEV4 routine performs spectral interpolation
from any grid to any grid for vector fields.
It requires that the input fields be uniformly global.
Options allow choices between triangular shape (ipopt(1)=0)
and Rhomboidal shape (ipopt(1)=1) which has no default;
A second option is the truncation (ipopt(2)) which defaults
to a sensible truncation for the input grid (if opt(2)=-1).
Note that if the output grid is not found in a special list,
then the transform back to grid is not very fast.
This special list contains global cylindrical grids,
Polar Stereographic grids centered at the pole and
Mercator grids. Only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
The input and output vectors are rotated so that they are
either resolved relative to the defined grid.
in the direction of increasing x and y coordinates
or resolved relative to easterly and northerly directions,
As designated by their respective grid description sections.
As an added bonus the number of output grid points and
their latitudes and longitudes are also returned along with
their vector rotation parameters.
On the other hand, the output can be a set of station points
if kgdso(1)<0, in which case the number of points
and their latitudes and longitudes must be input
along with their vector rotation parameters.
output bitmaps will only be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV4(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
& NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1)=0 FOR TRIANGULAR, IPOPT(1)=1 FOR RHOMBOIDAL;
IPOPT(2) IS TRUNCATION NUMBER
(DEFAULTS TO SENSIBLE IF IPOPT(2)=-1).
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
(KGDSO(1)<0 IMPLIES RANDOM STATION POINTS)
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS (MUST BE ALL 0)
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)<0)
RLAT - REAL (NO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)<0)
RLON - REAL (NO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)<0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)<0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)<0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS (ONLY IF KGDSO(1)>=0)
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES (IF KGDSO(1)>=0)
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES (IF KGDSO(1)>=0)
CROT - REAL (NO) VECTOR ROTATION COSINES (IF KGDSO(1)>=0)
SROT - REAL (NO) VECTOR ROTATION SINES (IF KGDSO(1)>=0)
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
41 INVALID NONGLOBAL INPUT GRID
42 INVALID SPECTRAL METHOD PARAMETERS
POLATEV6
The POLATEV6 routine performs budget interpolation
from any grid to any grid for vector fields.
It requires a grid for the output fields (kgdso(1)>=0).
The algorithm simply computes (weighted) averages
of neighbor points arranged in a square box
centered around each output grid point and stretching
nearly halfway to each of the neighboring grid points.
Options allow choices of number of points in each radius
from the center point (IPOPT(1)) which defaults to 2
(if ipopt(1)=-1) meaning that 25 points will be averaged;
Further options are the respective weights for the radius
points starting at the center point (ipopt(2:2+ipopt(1))
which defaults to all 1 (if ipopt(1)=-1 or ipopt(2)=-1).
Another option is the minimum percentage for mask,
i.e. percent valid input data required to make output data,
(ipopt(3+ipopt(1)) which defaults to 50 (if -1).
only horizontal interpolation is performed.
The grids are defined by their grid description sections
(passed in integer form as decoded by subprogram w3fi63).
The current code recognizes the following projections:
(KGDS(1)=000) EQUIDISTANT CYLINDRICAL
(KGDS(1)=001) MERCATOR CYLINDRICAL
(KGDS(1)=003) LAMBERT CONFORMAL CONICAL
(KGDS(1)=004) GAUSSIAN CYLINDRICAL (SPECTRAL NATIVE)
(KGDS(1)=005) POLAR STEREOGRAPHIC AZIMUTHAL
(KGDS(1)=202) ROTATED EQUIDISTANT CYLINDRICAL (ETA NATIVE)
Where KGDS could be either input KGDSI or output KGDSO.
The input and output vectors are rotated so that they are
either resolved relative to the defined grid
in the direction of increasing x and y coordinates
or resolved relative to easterly and northerly directions,
As designated by their respective grid description sections.
As an added bonus the number of output grid points
and their latitudes and longitudes are also returned
along with their vector rotation parameters.
input bitmaps will be interpolated to output bitmaps.
output bitmaps will also be created when the output grid
extends outside of the domain of the input grid.
The output field is set to 0 where the output bitmap is off.
USAGE: CALL POLATEV6(IPOPT,KGDSI,KGDSO,MI,MO,KM,IBI,LI,UI,VI,
NO,RLAT,RLON,CROT,SROT,IBO,LO,UO,VO,IRET)
Input argument list:
IPOPT - INTEGER (20) INTERPOLATION OPTIONS
IPOPT(1) IS NUMBER OF RADIUS POINTS
(DEFAULTS TO 2 IF IPOPT(1)=-1);
IPOPT(2:2+IPOPT(1)) ARE RESPECTIVE WEIGHTS
(DEFAULTS TO ALL 1 IF IPOPT(1)=-1 OR IPOPT(2)=-1).
IPOPT(3+IPOPT(1)) IS MINIMUM PERCENTAGE FOR MASK
(DEFAULTS TO 50 IF IPOPT(3+IPOPT(1)=-1)
KGDSI - INTEGER (200) INPUT GDS PARAMETERS AS DECODED BY W3FI63
KGDSO - INTEGER (200) OUTPUT GDS PARAMETERS
MI - INTEGER SKIP NUMBER BETWEEN INPUT GRID FIELDS IF KM>1
OR DIMENSION OF INPUT GRID FIELDS IF KM=1
MO - INTEGER SKIP NUMBER BETWEEN OUTPUT GRID FIELDS IF KM>1
OR DIMENSION OF OUTPUT GRID FIELDS IF KM=1
KM - INTEGER NUMBER OF FIELDS TO INTERPOLATE
IBI - INTEGER (KM) INPUT BITMAP FLAGS
LI - LOGICAL*1 (MI,KM) INPUT BITMAPS (IF SOME IBI(K)=1)
UI - REAL (MI,KM) INPUT U-COMPONENT FIELDS TO INTERPOLATE
VI - REAL (MI,KM) INPUT V-COMPONENT FIELDS TO INTERPOLATE
Output argument list:
NO - INTEGER NUMBER OF OUTPUT POINTS
RLAT - REAL (MO) OUTPUT LATITUDES IN DEGREES
RLON - REAL (MO) OUTPUT LONGITUDES IN DEGREES
CROT - REAL (NO) VECTOR ROTATION COSINES
SROT - REAL (NO) VECTOR ROTATION SINES
(UGRID=CROT*UEARTH-SROT*VEARTH;
VGRID=SROT*UEARTH+CROT*VEARTH)
IBO - INTEGER (KM) OUTPUT BITMAP FLAGS
LO - LOGICAL*1 (MO,KM) OUTPUT BITMAPS (ALWAYS OUTPUT)
UO - REAL (MO,KM) OUTPUT U-COMPONENT FIELDS INTERPOLATED
VO - REAL (MO,KM) OUTPUT V-COMPONENT FIELDS INTERPOLATED
IRET - INTEGER RETURN CODE
0 SUCCESSFUL INTERPOLATION
2 UNRECOGNIZED INPUT GRID OR NO GRID OVERLAP
3 UNRECOGNIZED OUTPUT GRID
31 INVALID UNDEFINED OUTPUT GRID
32 INVALID BUDGET METHOD PARAMETERS
POLFIXS
The POLFIXS routine averages multiple pole scalar values
on a latitude/longitude grid. Bitmaps may be averaged too.
USAGE: CALL POLFIXS(NM,NX,KM,RLAT,RLON,IB,LO,GO)
Input argument list:
NO - INTEGER NUMBER OF GRID POINTS
NX - INTEGER LEADING DIMENSION OF FIELDS
KM - INTEGER NUMBER OF FIELDS
RLAT - REAL (NO) LATITUDES IN DEGREES
RLON - REAL (NO) LONGITUDES IN DEGREES
IB - INTEGER (KM) BITMAP FLAGS
LO - LOGICAL*1 (NX,KM) BITMAPS (IF SOME IB(K)=1)
GO - REAL (NX,KM) FIELDS
Output argument list:
LO - LOGICAL*1 (NX,KM) BITMAPS (IF SOME IB(K)=1)
GO - REAL (NX,KM) FIELDS
POLFIXV
The POLFIXV routine averages multiple pole vector values
on a latitude/longitude grid. Bitmaps may be averaged too.
Vectors are rotated with respect to their longitude.
USAGE: CALL POLFIXV(NM,NX,KM,RLAT,RLON,IB,LO,UO,VO)
Input argument list:
NO - INTEGER NUMBER OF GRID POINTS
NX - INTEGER LEADING DIMENSION OF FIELDS
KM - INTEGER NUMBER OF FIELDS
RLAT - REAL (NO) LATITUDES IN DEGREES
RLON - REAL (NO) LONGITUDES IN DEGREES
IB - INTEGER (KM) BITMAP FLAGS
LO - LOGICAL*1 (NX,KM) BITMAPS (IF SOME IB(K)=1)
UO - REAL (NX,KM) U-WINDS
VO - REAL (NX,KM) V-WINDS
Output argument list:
LO - LOGICAL*1 (NX,KM) BITMAPS (IF SOME IB(K)=1)
UO - REAL (NX,KM) U-WINDS
VO - REAL (NX,KM) V-WINDS
| iplib.tar |
Library contains subroutines to be used for
interpolating almost any grids used at NCEP. (Fortran90)
Date posted: 9/05/2012 |