SPTEZD

The SPTEZD routine performs a spherical transform
           between spectral coefficients of a scalar field
           and its mean and gradient on a global cylindrical grid.
           The wave-space can be either Triangular or Rhomboidal.
           The grid-space can be either an equally-spaced grid
           (with or without pole points) or a Gaussian grid.
           The wave field is in sequential 'IBM order'.
           The grid fiels is indexed East to West, then North to South.
           For more flexibility and efficiency, call SPTRAN.
           Subprogram can be called from a multiprocessing environment.

USAGE:    CALL SPTEZD(IROMB,MAXWV,IDRT,IMAX,JMAX,
                      WAVE,GRIDMN,GRIDX,GRIDY,IDIR)

   Input arguments:
      IROMB    - INTEGER SPECTRAL DOMAIN SHAPE
                 (0 FOR TRIANGULAR, 1 FOR RHOMBOIDAL)
      MAXWV    - INTEGER SPECTRAL TRUNCATION
      IDRT     - INTEGER GRID IDENTIFIER
                 (IDRT=4 FOR GAUSSIAN GRID,
                  IDRT=0 FOR EQUALLY-SPACED GRID INCLUDING POLES,
                  IDRT=256 FOR EQUALLY-SPACED GRID EXCLUDING POLES)
      IMAX     - INTEGER EVEN NUMBER OF LONGITUDES.
      JMAX     - INTEGER NUMBER OF LATITUDES.
      WAVE     - REAL (*) WAVE FIELD IF IDIR>0
      GRIDMN   - REAL GLOBAL MEAN IF IDIR<0
      GRIDX    - REAL (IMAX,JMAX) GRID X-GRADIENTS (E->W,N->S) IF IDIR<0
      GRIDY    - REAL (IMAX,JMAX) GRID Y-GRADIENTS (E->W,N->S) IF IDIR<0
      IDIR     - INTEGER TRANSFORM FLAG
                 (IDIR>0 FOR WAVE TO GRID, IDIR<0 FOR GRID TO WAVE)

   Output arguments:
      WAVE     - REAL (*) WAVE FIELD IF IDIR<0
      GRIDMN   - REAL GLOBAL MEAN IF IDIR>0
      GRIDX    - REAL (IMAX,JMAX) GRID X-GRADIENTS (E->W,N->S) IF IDIR>0
      GRIDY    - REAL (IMAX,JMAX) GRID Y-GRADIENTS (E->W,N->S) IF IDIR>0

REMARKS:
        MINIMUM GRID DIMENSIONS FOR UNALIASED TRANSFORMS TO SPECTRAL:

    DIMENSION                    LINEAR              QUADRATIC
    -----------------------      ---------           -------------
    IMAX                         2*MAXWV+2           3*MAXWV/2*2+2
    JMAX (IDRT=4,IROMB=0)        1*MAXWV+1           3*MAXWV/2+1
    JMAX (IDRT=4,IROMB=1)        2*MAXWV+1           5*MAXWV/2+1
    JMAX (IDRT=0,IROMB=0)        2*MAXWV+3           3*MAXWV/2*2+3
    JMAX (IDRT=0,IROMB=1)        4*MAXWV+3           5*MAXWV/2*2+3
    JMAX (IDRT=256,IROMB=0)      2*MAXWV+1           3*MAXWV/2*2+1
    JMAX (IDRT=256,IROMB=1)      4*MAXWV+1           5*MAXWV/2*2+1
 
 


  
SPLIB.tar
  
Library contains routines to be
   be used for a variety of spectral transform functions. (Fortran90) 

   Date posted: 2/23/2007