NCEPLIBS-ip  5.0.0
speps.f File Reference

Compute utility spectral fields. More...

Go to the source code of this file.

Functions/Subroutines

subroutine speps (I, M, EPS, EPSTOP, ENN1, ELONN1, EON, EONTOP)
 Computes constant fields indexed in the spectral domain in "IBM ORDER" (Zonal wavenumber is the slower index). More...
 

Detailed Description

Compute utility spectral fields.

Author
Iredell
Date
92-10-31

Definition in file speps.f.

Function/Subroutine Documentation

◆ speps()

subroutine speps (   I,
  M,
real, dimension((m+1)*((i+1)*m+2)/2)  EPS,
real, dimension(m+1)  EPSTOP,
real, dimension((m+1)*((i+1)*m+2)/2)  ENN1,
real, dimension((m+1)*((i+1)*m+2)/2)  ELONN1,
real, dimension((m+1)*((i+1)*m+2)/2)  EON,
real, dimension(m+1)  EONTOP 
)

Computes constant fields indexed in the spectral domain in "IBM ORDER" (Zonal wavenumber is the slower index).

If L is the zonal wavenumber and N is the total wavenumber and A is the earth radius, then the fields returned are:

  • (1) normalizing factor EPSILON=SQRT((N**2-L**2)/(4*N**2-1))
  • (2) Laplacian factor N*(N+1)/A**2
  • (3) zonal derivative/Laplacian factor L/(N*(N+1))*A
  • (4) Meridional derivative/Laplacian factor EPSILON/N*A
Parameters
Ispectral domain shape (0 for triangular, 1 for rhomboidal)
Mspectral truncation
EPS((M+1)*((I+1)*M+2)/2) SQRT((N**2-L**2)/(4*N**2-1))
EPSTOP(M+1) SQRT((N**2-L**2)/(4*N**2-1)) OVER TOP
ENN1((M+1)*((I+1)*M+2)/2) N*(N+1)/A**2
ELONN1((M+1)*((I+1)*M+2)/2) L/(N*(N+1))*A
EON((M+1)*((I+1)*M+2)/2) EPSILON/N*A
EONTOP(M+1) EPSILON/N*A OVER TOP
Author
Iredell
Date
92-10-31

Definition at line 25 of file speps.f.

Referenced by spwget().