w3ft21.f File Reference

Go to the source code of this file.

Functions/Subroutines
subroutine	w3ft21 (FLN, GN, PLN, EPS, FL, WORK, TRIGS, L1, L2, I2)
	SUBPROGRAM: W3FT21 COMPUTES 2.5 X 2.5 N. More...

Function/Subroutine Documentation

w3ft21()

subroutine w3ft21	(	complex, dimension (31,31)	FLN,
		real, dimension (145,37)	GN,
		real, dimension (32,31)	PLN,
		real, dimension (992)	EPS,
		complex, dimension (31)	FL,
		real, dimension (144)	WORK,
		real, dimension (216)	TRIGS,
			L1,
			L2,
			I2
	)

SUBPROGRAM: W3FT21 COMPUTES 2.5 X 2.5 N.

HEMI. GRID-SCALER AUTHOR: JONES,R.E. ORG: W342 DATE: 81-11-19

ABSTRACT: COMPUTES 2.5 X 2.5 N. HEMI. GRID OF 145 X 37 POINTS FROM SPECTRAL COEFFICIENTS IN A RHOMBOIDAL 30 RESOLUTION REPRESENTING A SCALAR FIELD. SPECIAL VERSION OF W3FT08 WHICH GIVES PROGRAMMER MORE CONTROL OF HOW MANY WAVES ARE SUMMED AND HOW MANY POINTS IN EACH WAVE. A PROGRAMMER CAN SIMULATE 24-MODE, 12-MODE, ETC.

PROGRAM HISTORY LOG: 81-11-19 R.E.JONES 84-06-01 R.E.JONES CHANGE TO IBM VS FORTRAN

USAGE: CALL W3FT21(FLN,GN,PLN,EPS,FL,WORK,TRIGS,L1,L2,I2)

INPUT VARIABLES: NAMES INTERFACE DESCRIPTION OF VARIABLES AND TYPES

---

FLN ARG LIST 961 COMPLEX COEFF. PLN ARG LIST 992 REAL SPACE FOR LEGENDRE POLYNOMIALS EPS ARG LIST 992 REAL SPACE FOR COEFFS. USED IN COMPUTING PLN. FL ARG LIST 31 COMPLEX SPACE FOR FOURIER COEFF. WORK ARG LIST 144 REAL WORK SPACE FOR SUBR. W3FT12 TRIGS ARG LIST 216 PRECOMPUTED TRIG FUNCS, USED IN W3FT12, COMPUTED BY W3FA13 L1 ARG LIST STARTING WAVE NUMBER L2 ARG LIST ENDING WAVE NUMBER I2 ARG LIST MODE OF SPECTRAL COEFFICIENTS

OUTPUT VARIABLES: NAMES INTERFACE DESCRIPTION OF VARIABLES AND TYPES

---

GN ARG LIST (145,37) GRID VALUES. 5365 POINT GRID IS TYPE 29 OR 1D HEX O.N. 84

SUBPROGRAMS CALLED: NAMES LIBRARY

---

AIMAG CMPLX REAL SYSLIB W3FA12 W3FT12 W3LIB

WARNING: THIS SUBROUTINE WAS OPTIMIZED TO RUN IN A SMALL AMOUNT OF MEMORY, IT IS NOT OPTIMIZED FOR SPEED, 70 PERCENT OF THE TIME IS USED BY SUBROUTINE W3FA12 COMPUTING THE LEGENDRE POLYNOMIALS. SINCE THE LEGENDRE POLYNOMIALS ARE CONSTANT THEY NEED TO BE COMPUTED ONLY ONCE IN A PROGRAM. BY MOVING W3FA12 TO THE MAIN PROGRAM AND COMPUTING PLN AS A (32,31,37) ARRAY AND CHANGING THIS SUBROUTINE TO USE PLN AS A THREE DIMENSION ARRAY YOU CAN CUT THE RUNNING TIME 70 PERCENT.

ATTRIBUTES: LANGUAGE: CRAY CFT77 FORTRAN MACHINE: CRAY C916, Y-MP8/64, Y-MP EL92/256

Definition at line 60 of file w3ft21.f.