/wrfv2_fire/external/fftpack/fftpack5/r1f4kb.F
FORTRAN Legacy | 69 lines | 42 code | 1 blank | 26 comment | 0 complexity | 2609ad97f8a4f5394abbe5d26bb650a6 MD5 | raw file
Possible License(s): AGPL-1.0
- !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
- !
- ! FFTPACK 5.0
- !
- ! Authors: Paul N. Swarztrauber and Richard A. Valent
- !
- ! $Id: r1f4kb.f,v 1.2 2004/06/15 21:29:20 rodney Exp $
- !
- !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
-
- SUBROUTINE R1F4KB (IDO,L1,CC,IN1,CH,IN2,WA1,WA2,WA3)
- REAL CC(IN1,IDO,4,L1) ,CH(IN2,IDO,L1,4) , &
- & WA1(IDO) , WA2(IDO) , WA3(IDO)
- !
- SQRT2=SQRT(2.)
- DO 101 K=1,L1
- CH(1,1,K,3) = (CC(1,1,1,K)+CC(1,IDO,4,K)) &
- & -(CC(1,IDO,2,K)+CC(1,IDO,2,K))
- CH(1,1,K,1) = (CC(1,1,1,K)+CC(1,IDO,4,K)) &
- & +(CC(1,IDO,2,K)+CC(1,IDO,2,K))
- CH(1,1,K,4) = (CC(1,1,1,K)-CC(1,IDO,4,K)) &
- & +(CC(1,1,3,K)+CC(1,1,3,K))
- CH(1,1,K,2) = (CC(1,1,1,K)-CC(1,IDO,4,K)) &
- & -(CC(1,1,3,K)+CC(1,1,3,K))
- 101 END DO
- IF (IDO-2) 107,105,102
- 102 IDP2 = IDO+2
- DO 104 K=1,L1
- DO 103 I=3,IDO,2
- IC = IDP2-I
- CH(1,I-1,K,1) = (CC(1,I-1,1,K)+CC(1,IC-1,4,K)) &
- & +(CC(1,I-1,3,K)+CC(1,IC-1,2,K))
- CH(1,I,K,1) = (CC(1,I,1,K)-CC(1,IC,4,K)) &
- & +(CC(1,I,3,K)-CC(1,IC,2,K))
- CH(1,I-1,K,2)=WA1(I-2)*((CC(1,I-1,1,K)-CC(1,IC-1,4,K)) &
- & -(CC(1,I,3,K)+CC(1,IC,2,K)))-WA1(I-1) &
- & *((CC(1,I,1,K)+CC(1,IC,4,K))+(CC(1,I-1,3,K)-CC(1,IC-1,2,K)))
- CH(1,I,K,2)=WA1(I-2)*((CC(1,I,1,K)+CC(1,IC,4,K)) &
- & +(CC(1,I-1,3,K)-CC(1,IC-1,2,K)))+WA1(I-1) &
- & *((CC(1,I-1,1,K)-CC(1,IC-1,4,K))-(CC(1,I,3,K)+CC(1,IC,2,K)))
- CH(1,I-1,K,3)=WA2(I-2)*((CC(1,I-1,1,K)+CC(1,IC-1,4,K)) &
- & -(CC(1,I-1,3,K)+CC(1,IC-1,2,K)))-WA2(I-1) &
- & *((CC(1,I,1,K)-CC(1,IC,4,K))-(CC(1,I,3,K)-CC(1,IC,2,K)))
- CH(1,I,K,3)=WA2(I-2)*((CC(1,I,1,K)-CC(1,IC,4,K)) &
- & -(CC(1,I,3,K)-CC(1,IC,2,K)))+WA2(I-1) &
- & *((CC(1,I-1,1,K)+CC(1,IC-1,4,K))-(CC(1,I-1,3,K) &
- & +CC(1,IC-1,2,K)))
- CH(1,I-1,K,4)=WA3(I-2)*((CC(1,I-1,1,K)-CC(1,IC-1,4,K)) &
- & +(CC(1,I,3,K)+CC(1,IC,2,K)))-WA3(I-1) &
- & *((CC(1,I,1,K)+CC(1,IC,4,K))-(CC(1,I-1,3,K)-CC(1,IC-1,2,K)))
- CH(1,I,K,4)=WA3(I-2)*((CC(1,I,1,K)+CC(1,IC,4,K)) &
- & -(CC(1,I-1,3,K)-CC(1,IC-1,2,K)))+WA3(I-1) &
- & *((CC(1,I-1,1,K)-CC(1,IC-1,4,K))+(CC(1,I,3,K)+CC(1,IC,2,K)))
- 103 CONTINUE
- 104 END DO
- IF (MOD(IDO,2) .EQ. 1) RETURN
- 105 CONTINUE
- DO 106 K=1,L1
- CH(1,IDO,K,1) = (CC(1,IDO,1,K)+CC(1,IDO,3,K)) &
- & +(CC(1,IDO,1,K)+CC(1,IDO,3,K))
- CH(1,IDO,K,2) = SQRT2*((CC(1,IDO,1,K)-CC(1,IDO,3,K)) &
- & -(CC(1,1,2,K)+CC(1,1,4,K)))
- CH(1,IDO,K,3) = (CC(1,1,4,K)-CC(1,1,2,K)) &
- & +(CC(1,1,4,K)-CC(1,1,2,K))
- CH(1,IDO,K,4) = -SQRT2*((CC(1,IDO,1,K)-CC(1,IDO,3,K)) &
- & +(CC(1,1,2,K)+CC(1,1,4,K)))
- 106 END DO
- 107 RETURN
- END