mirror of
https://git.planet-casio.com/Lephenixnoir/OpenLibm.git
synced 2025-01-01 06:23:39 +01:00
143 lines
5.1 KiB
Fortran
143 lines
5.1 KiB
Fortran
*DECK PASSF5
|
|
SUBROUTINE PASSF5 (IDO, L1, CC, CH, WA1, WA2, WA3, WA4)
|
|
C***BEGIN PROLOGUE PASSF5
|
|
C***SUBSIDIARY
|
|
C***PURPOSE Calculate the fast Fourier transform of subvectors of
|
|
C length five.
|
|
C***LIBRARY SLATEC (FFTPACK)
|
|
C***TYPE SINGLE PRECISION (PASSF5-S)
|
|
C***AUTHOR Swarztrauber, P. N., (NCAR)
|
|
C***ROUTINES CALLED (NONE)
|
|
C***REVISION HISTORY (YYMMDD)
|
|
C 790601 DATE WRITTEN
|
|
C 830401 Modified to use SLATEC library source file format.
|
|
C 860115 Modified by Ron Boisvert to adhere to Fortran 77 by
|
|
C (a) changing dummy array size declarations (1) to (*),
|
|
C (b) changing definition of variables PI, TI11, TI12,
|
|
C TR11, TR12 by using FORTRAN intrinsic functions ATAN
|
|
C and SIN instead of DATA statements.
|
|
C 881128 Modified by Dick Valent to meet prologue standards.
|
|
C 890831 Modified array declarations. (WRB)
|
|
C 891214 Prologue converted to Version 4.0 format. (BAB)
|
|
C 900402 Added TYPE section. (WRB)
|
|
C***END PROLOGUE PASSF5
|
|
DIMENSION CC(IDO,5,*), CH(IDO,L1,5), WA1(*), WA2(*), WA3(*),
|
|
+ WA4(*)
|
|
C***FIRST EXECUTABLE STATEMENT PASSF5
|
|
PI = 4.*ATAN(1.)
|
|
TR11 = SIN(.1*PI)
|
|
TI11 = -SIN(.4*PI)
|
|
TR12 = -SIN(.3*PI)
|
|
TI12 = -SIN(.2*PI)
|
|
IF (IDO .NE. 2) GO TO 102
|
|
DO 101 K=1,L1
|
|
TI5 = CC(2,2,K)-CC(2,5,K)
|
|
TI2 = CC(2,2,K)+CC(2,5,K)
|
|
TI4 = CC(2,3,K)-CC(2,4,K)
|
|
TI3 = CC(2,3,K)+CC(2,4,K)
|
|
TR5 = CC(1,2,K)-CC(1,5,K)
|
|
TR2 = CC(1,2,K)+CC(1,5,K)
|
|
TR4 = CC(1,3,K)-CC(1,4,K)
|
|
TR3 = CC(1,3,K)+CC(1,4,K)
|
|
CH(1,K,1) = CC(1,1,K)+TR2+TR3
|
|
CH(2,K,1) = CC(2,1,K)+TI2+TI3
|
|
CR2 = CC(1,1,K)+TR11*TR2+TR12*TR3
|
|
CI2 = CC(2,1,K)+TR11*TI2+TR12*TI3
|
|
CR3 = CC(1,1,K)+TR12*TR2+TR11*TR3
|
|
CI3 = CC(2,1,K)+TR12*TI2+TR11*TI3
|
|
CR5 = TI11*TR5+TI12*TR4
|
|
CI5 = TI11*TI5+TI12*TI4
|
|
CR4 = TI12*TR5-TI11*TR4
|
|
CI4 = TI12*TI5-TI11*TI4
|
|
CH(1,K,2) = CR2-CI5
|
|
CH(1,K,5) = CR2+CI5
|
|
CH(2,K,2) = CI2+CR5
|
|
CH(2,K,3) = CI3+CR4
|
|
CH(1,K,3) = CR3-CI4
|
|
CH(1,K,4) = CR3+CI4
|
|
CH(2,K,4) = CI3-CR4
|
|
CH(2,K,5) = CI2-CR5
|
|
101 CONTINUE
|
|
RETURN
|
|
102 IF(IDO/2.LT.L1) GO TO 105
|
|
DO 104 K=1,L1
|
|
CDIR$ IVDEP
|
|
DO 103 I=2,IDO,2
|
|
TI5 = CC(I,2,K)-CC(I,5,K)
|
|
TI2 = CC(I,2,K)+CC(I,5,K)
|
|
TI4 = CC(I,3,K)-CC(I,4,K)
|
|
TI3 = CC(I,3,K)+CC(I,4,K)
|
|
TR5 = CC(I-1,2,K)-CC(I-1,5,K)
|
|
TR2 = CC(I-1,2,K)+CC(I-1,5,K)
|
|
TR4 = CC(I-1,3,K)-CC(I-1,4,K)
|
|
TR3 = CC(I-1,3,K)+CC(I-1,4,K)
|
|
CH(I-1,K,1) = CC(I-1,1,K)+TR2+TR3
|
|
CH(I,K,1) = CC(I,1,K)+TI2+TI3
|
|
CR2 = CC(I-1,1,K)+TR11*TR2+TR12*TR3
|
|
CI2 = CC(I,1,K)+TR11*TI2+TR12*TI3
|
|
CR3 = CC(I-1,1,K)+TR12*TR2+TR11*TR3
|
|
CI3 = CC(I,1,K)+TR12*TI2+TR11*TI3
|
|
CR5 = TI11*TR5+TI12*TR4
|
|
CI5 = TI11*TI5+TI12*TI4
|
|
CR4 = TI12*TR5-TI11*TR4
|
|
CI4 = TI12*TI5-TI11*TI4
|
|
DR3 = CR3-CI4
|
|
DR4 = CR3+CI4
|
|
DI3 = CI3+CR4
|
|
DI4 = CI3-CR4
|
|
DR5 = CR2+CI5
|
|
DR2 = CR2-CI5
|
|
DI5 = CI2-CR5
|
|
DI2 = CI2+CR5
|
|
CH(I-1,K,2) = WA1(I-1)*DR2+WA1(I)*DI2
|
|
CH(I,K,2) = WA1(I-1)*DI2-WA1(I)*DR2
|
|
CH(I-1,K,3) = WA2(I-1)*DR3+WA2(I)*DI3
|
|
CH(I,K,3) = WA2(I-1)*DI3-WA2(I)*DR3
|
|
CH(I-1,K,4) = WA3(I-1)*DR4+WA3(I)*DI4
|
|
CH(I,K,4) = WA3(I-1)*DI4-WA3(I)*DR4
|
|
CH(I-1,K,5) = WA4(I-1)*DR5+WA4(I)*DI5
|
|
CH(I,K,5) = WA4(I-1)*DI5-WA4(I)*DR5
|
|
103 CONTINUE
|
|
104 CONTINUE
|
|
RETURN
|
|
105 DO 107 I=2,IDO,2
|
|
CDIR$ IVDEP
|
|
DO 106 K=1,L1
|
|
TI5 = CC(I,2,K)-CC(I,5,K)
|
|
TI2 = CC(I,2,K)+CC(I,5,K)
|
|
TI4 = CC(I,3,K)-CC(I,4,K)
|
|
TI3 = CC(I,3,K)+CC(I,4,K)
|
|
TR5 = CC(I-1,2,K)-CC(I-1,5,K)
|
|
TR2 = CC(I-1,2,K)+CC(I-1,5,K)
|
|
TR4 = CC(I-1,3,K)-CC(I-1,4,K)
|
|
TR3 = CC(I-1,3,K)+CC(I-1,4,K)
|
|
CH(I-1,K,1) = CC(I-1,1,K)+TR2+TR3
|
|
CH(I,K,1) = CC(I,1,K)+TI2+TI3
|
|
CR2 = CC(I-1,1,K)+TR11*TR2+TR12*TR3
|
|
CI2 = CC(I,1,K)+TR11*TI2+TR12*TI3
|
|
CR3 = CC(I-1,1,K)+TR12*TR2+TR11*TR3
|
|
CI3 = CC(I,1,K)+TR12*TI2+TR11*TI3
|
|
CR5 = TI11*TR5+TI12*TR4
|
|
CI5 = TI11*TI5+TI12*TI4
|
|
CR4 = TI12*TR5-TI11*TR4
|
|
CI4 = TI12*TI5-TI11*TI4
|
|
DR3 = CR3-CI4
|
|
DR4 = CR3+CI4
|
|
DI3 = CI3+CR4
|
|
DI4 = CI3-CR4
|
|
DR5 = CR2+CI5
|
|
DR2 = CR2-CI5
|
|
DI5 = CI2-CR5
|
|
DI2 = CI2+CR5
|
|
CH(I-1,K,2) = WA1(I-1)*DR2+WA1(I)*DI2
|
|
CH(I,K,2) = WA1(I-1)*DI2-WA1(I)*DR2
|
|
CH(I-1,K,3) = WA2(I-1)*DR3+WA2(I)*DI3
|
|
CH(I,K,3) = WA2(I-1)*DI3-WA2(I)*DR3
|
|
CH(I-1,K,4) = WA3(I-1)*DR4+WA3(I)*DI4
|
|
CH(I,K,4) = WA3(I-1)*DI4-WA3(I)*DR4
|
|
CH(I-1,K,5) = WA4(I-1)*DR5+WA4(I)*DI5
|
|
CH(I,K,5) = WA4(I-1)*DI5-WA4(I)*DR5
|
|
106 CONTINUE
|
|
107 CONTINUE
|
|
RETURN
|
|
END
|