W3FT00
The W3FT00 routine transforms data contained in a grid
array by translation, rotation about a common point
and dilatation to a new grid array.
USAGE: CALL W3FT00 (FA,FB,IA,JA,IB,JB,AIP,AJP,BIP,BJP,SC,ARG,LIN)
Input argument list:
FA REAL ORIGIONAL FIELD DIMENSIONED (IA,IJ)
IA INTEGER I-DIMENSION OF THE INPUT ARRAY FA
JA INTEGER J-DIMENSION OF THE INPUT ARRAY FA
IB INTEGER I-DIMENSION OF THE OUTPUT ARRAY FB
JB INTEGER J-DIMENSION OF THE OUTPUT ARRAY FB
AIP REAL COMMON POINT I-COORDINATE OF THE ORIGIONAL
FIELD ASSUMING A RIGHT HAND CARTESIAN COORDINATE
SYSTEM. THE POINT NEED NOT BE IN EITHER GRID AND
CAN HAVE FRACTIONAL INDICES).
AJP REAL COMMON POINT J-COORDINATE AS AIP ABOVE
BIP REAL COMMON POINT I-COORDINATE FOR TRANSFORMED
GRID
BJP REAL COMMON POINT J-COORDINATE FOR TRANSFORMED
GRID
SC REAL SCALE CHANGE (DILATION) EXPRESSED AS
A RATIO OF THE TRANSFORMED TO THE ORIGIONAL FIELD
ARG REAL DEGREE MEASURE OF THE ANGLE REQUIRED TO
ROTATE THE J-ROW OF THE ORIGIONAL GRID INTO
COINCIDENCE WITH THE NEW GRID. (+ COUNTER-
CLOCKWISE, - CLOCKWISE)
LIN INTEGER INTERPOLATION METHOD SWITCH
.EQ. 1 BILINEAR INTERPOLATION
.NE. 1 BIQUADRATIC INTERPOLATION
Output argument list:
FB REAL TRANSFORMED FIELD DIMENSIONED (IB,JB)
REMARKS:
IN GENERAL 'FA' AND 'FB' CANNOT BE EQUIVALENCED
ALTHOUGH THERE ARE SITUATIONS IN WHICH IT WOULD BE SAFE TO DO
SO. CARE SHOULD BE TAKEN THAT ALL OF THE NEW GRID POINTS LIE
WITHIN THE ORIGIONAL GRID, NO ERROR CHECKS ARE MADE.
W3lib.tar |
Library contains Fortran 90 decoder/encoder
routines for GRIB edition 1. (Fortran90)
Date posted: 2/22/2007 |