NCEPLIBS-sp 2.4.0
sptezm.f File Reference

Perform simple scalar spherical transforms. More...

Go to the source code of this file.

Functions/Subroutines

subroutine sptezm (IROMB, MAXWV, IDRT, IMAX, JMAX, KMAX, WAVE, GRID, IDIR)
 This subprogram performs spherical transforms between spectral coefficients of scalar quantities and fields on a global cylindrical grid. More...
 

Detailed Description

Perform simple scalar spherical transforms.

Author
Iredell
Date
96-02-29

Definition in file sptezm.f.

Function/Subroutine Documentation

◆ sptezm()

subroutine sptezm (   IROMB,
  MAXWV,
  IDRT,
  IMAX,
  JMAX,
  KMAX,
real, dimension((maxwv+1)*((iromb+1)*maxwv+2),kmax)  WAVE,
real, dimension(imax,jmax,kmax)  GRID,
  IDIR 
)

This subprogram performs spherical transforms between spectral coefficients of scalar quantities and fields 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.

Wave fields are in sequential 'IBM ORDER'.

Grid fields are indexed East to West, then North to South.

For more flexibility and efficiency, call sptran().

Subprogram can be called from a multiprocessing environment.

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
Parameters
IROMBspectral domain shape (0 for triangular, 1 for rhomboidal)
MAXWVspectral truncation
IDRTgrid identifier
  • IDRT=4 for Gaussian grid
  • IDRT=0 for equally-spaced grid including poles
  • IDRT=256 for equally-spaced grid excluding poles
IMAXeven number of longitudes
JMAXnumber of latitudes
KMAXnumber of fields to transform
[out]WAVEwave field if IDIR>0 where MX=(MAXWV+1)*((IROMB+1)*MAXWV+2)/2
[out]GRIDgrid field (E->W,N->S) if IDIR<0
IDIRtransform flag (IDIR>0 for wave to grid, IDIR<0 for grid to wave).
Author
Iredell
Date
96-02-29

Definition at line 50 of file sptezm.f.

References ncpus(), and sptranf().