wrfv2_fire/external/fftpack/fftpack5/c1f4kf.F

   1 !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
   2 !
   3 !   FFTPACK 5.0
   4 !
   5 !   Authors:  Paul N. Swarztrauber and Richard A. Valent
   6 !
   7 !   $Id: c1f4kf.f,v 1.2 2004/06/15 21:08:32 rodney Exp $
   8 !
   9 !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
  10
  11       SUBROUTINE C1F4KF (IDO,L1,NA,CC,IN1,CH,IN2,WA)
  12       REAL CC(IN1,L1,IDO,4),CH(IN2,L1,4,IDO),WA(IDO,3,2)
  13 !
  14 ! FFTPACK 5.0 auxiliary routine
  15 !
  16       IF (IDO .GT. 1) GO TO 102
  17       SN = 1./REAL(4*L1)
  18       IF (NA .EQ. 1) GO TO 106
  19       DO 101 K=1,L1
  20          TI1 = CC(2,K,1,1)-CC(2,K,1,3)
  21          TI2 = CC(2,K,1,1)+CC(2,K,1,3)
  22          TR4 = CC(2,K,1,2)-CC(2,K,1,4)
  23          TI3 = CC(2,K,1,2)+CC(2,K,1,4)
  24          TR1 = CC(1,K,1,1)-CC(1,K,1,3)
  25          TR2 = CC(1,K,1,1)+CC(1,K,1,3)
  26          TI4 = CC(1,K,1,4)-CC(1,K,1,2)
  27          TR3 = CC(1,K,1,2)+CC(1,K,1,4)
  28          CC(1,K,1,1) = SN*(TR2+TR3)
  29          CC(1,K,1,3) = SN*(TR2-TR3)
  30          CC(2,K,1,1) = SN*(TI2+TI3)
  31          CC(2,K,1,3) = SN*(TI2-TI3)
  32          CC(1,K,1,2) = SN*(TR1+TR4)
  33          CC(1,K,1,4) = SN*(TR1-TR4)
  34          CC(2,K,1,2) = SN*(TI1+TI4)
  35          CC(2,K,1,4) = SN*(TI1-TI4)
  36   101 END DO
  37       RETURN
  38   106 DO 107 K=1,L1
  39          TI1 = CC(2,K,1,1)-CC(2,K,1,3)
  40          TI2 = CC(2,K,1,1)+CC(2,K,1,3)
  41          TR4 = CC(2,K,1,2)-CC(2,K,1,4)
  42          TI3 = CC(2,K,1,2)+CC(2,K,1,4)
  43          TR1 = CC(1,K,1,1)-CC(1,K,1,3)
  44          TR2 = CC(1,K,1,1)+CC(1,K,1,3)
  45          TI4 = CC(1,K,1,4)-CC(1,K,1,2)
  46          TR3 = CC(1,K,1,2)+CC(1,K,1,4)
  47          CH(1,K,1,1) = SN*(TR2+TR3)
  48          CH(1,K,3,1) = SN*(TR2-TR3)
  49          CH(2,K,1,1) = SN*(TI2+TI3)
  50          CH(2,K,3,1) = SN*(TI2-TI3)
  51          CH(1,K,2,1) = SN*(TR1+TR4)
  52          CH(1,K,4,1) = SN*(TR1-TR4)
  53          CH(2,K,2,1) = SN*(TI1+TI4)
  54          CH(2,K,4,1) = SN*(TI1-TI4)
  55   107 END DO
  56       RETURN
  57   102 DO 103 K=1,L1
  58          TI1 = CC(2,K,1,1)-CC(2,K,1,3)
  59          TI2 = CC(2,K,1,1)+CC(2,K,1,3)
  60          TR4 = CC(2,K,1,2)-CC(2,K,1,4)
  61          TI3 = CC(2,K,1,2)+CC(2,K,1,4)
  62          TR1 = CC(1,K,1,1)-CC(1,K,1,3)
  63          TR2 = CC(1,K,1,1)+CC(1,K,1,3)
  64          TI4 = CC(1,K,1,4)-CC(1,K,1,2)
  65          TR3 = CC(1,K,1,2)+CC(1,K,1,4)
  66          CH(1,K,1,1) = TR2+TR3
  67          CH(1,K,3,1) = TR2-TR3
  68          CH(2,K,1,1) = TI2+TI3
  69          CH(2,K,3,1) = TI2-TI3
  70          CH(1,K,2,1) = TR1+TR4
  71          CH(1,K,4,1) = TR1-TR4
  72          CH(2,K,2,1) = TI1+TI4
  73          CH(2,K,4,1) = TI1-TI4
  74   103 END DO
  75       DO 105 I=2,IDO
  76          DO 104 K=1,L1
  77             TI1 = CC(2,K,I,1)-CC(2,K,I,3)
  78             TI2 = CC(2,K,I,1)+CC(2,K,I,3)
  79             TI3 = CC(2,K,I,2)+CC(2,K,I,4)
  80             TR4 = CC(2,K,I,2)-CC(2,K,I,4)
  81             TR1 = CC(1,K,I,1)-CC(1,K,I,3)
  82             TR2 = CC(1,K,I,1)+CC(1,K,I,3)
  83             TI4 = CC(1,K,I,4)-CC(1,K,I,2)
  84             TR3 = CC(1,K,I,2)+CC(1,K,I,4)
  85             CH(1,K,1,I) = TR2+TR3
  86             CR3 = TR2-TR3
  87             CH(2,K,1,I) = TI2+TI3
  88             CI3 = TI2-TI3
  89             CR2 = TR1+TR4
  90             CR4 = TR1-TR4
  91             CI2 = TI1+TI4
  92             CI4 = TI1-TI4
  93             CH(1,K,2,I) = WA(I,1,1)*CR2+WA(I,1,2)*CI2
  94             CH(2,K,2,I) = WA(I,1,1)*CI2-WA(I,1,2)*CR2
  95             CH(1,K,3,I) = WA(I,2,1)*CR3+WA(I,2,2)*CI3
  96             CH(2,K,3,I) = WA(I,2,1)*CI3-WA(I,2,2)*CR3
  97             CH(1,K,4,I) = WA(I,3,1)*CR4+WA(I,3,2)*CI4
  98             CH(2,K,4,I) = WA(I,3,1)*CI4-WA(I,3,2)*CR4
  99   104    CONTINUE
 100   105 END DO
 101       RETURN
 102       END