| blob | da025ec4f3ed40ffcccf019d037de0423e085e49 |
1 !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
2 !
3 ! FFTPACK 5.0
4 ! Copyright (C) 1995-2004, Scientific Computing Division,
5 ! University Corporation for Atmospheric Research
6 ! Licensed under the GNU General Public License (GPL)
7 !
8 ! Authors: Paul N. Swarztrauber and Richard A. Valent
9 !
10 ! $Id: c1f4kf.f,v 1.2 2004/06/15 21:08:32 rodney Exp $
11 !
12 !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
14 SUBROUTINE C1F4KF (IDO,L1,NA,CC,IN1,CH,IN2,WA)
15 REAL CC(IN1,L1,IDO,4),CH(IN2,L1,4,IDO),WA(IDO,3,2)
16 !
17 ! FFTPACK 5.0 auxiliary routine
18 !
19 IF (IDO .GT. 1) GO TO 102
20 SN = 1./REAL(4*L1)
21 IF (NA .EQ. 1) GO TO 106
22 DO 101 K=1,L1
23 TI1 = CC(2,K,1,1)-CC(2,K,1,3)
24 TI2 = CC(2,K,1,1)+CC(2,K,1,3)
25 TR4 = CC(2,K,1,2)-CC(2,K,1,4)
26 TI3 = CC(2,K,1,2)+CC(2,K,1,4)
27 TR1 = CC(1,K,1,1)-CC(1,K,1,3)
28 TR2 = CC(1,K,1,1)+CC(1,K,1,3)
29 TI4 = CC(1,K,1,4)-CC(1,K,1,2)
30 TR3 = CC(1,K,1,2)+CC(1,K,1,4)
31 CC(1,K,1,1) = SN*(TR2+TR3)
32 CC(1,K,1,3) = SN*(TR2-TR3)
33 CC(2,K,1,1) = SN*(TI2+TI3)
34 CC(2,K,1,3) = SN*(TI2-TI3)
35 CC(1,K,1,2) = SN*(TR1+TR4)
36 CC(1,K,1,4) = SN*(TR1-TR4)
37 CC(2,K,1,2) = SN*(TI1+TI4)
38 CC(2,K,1,4) = SN*(TI1-TI4)
39 101 END DO
40 RETURN
41 106 DO 107 K=1,L1
42 TI1 = CC(2,K,1,1)-CC(2,K,1,3)
43 TI2 = CC(2,K,1,1)+CC(2,K,1,3)
44 TR4 = CC(2,K,1,2)-CC(2,K,1,4)
45 TI3 = CC(2,K,1,2)+CC(2,K,1,4)
46 TR1 = CC(1,K,1,1)-CC(1,K,1,3)
47 TR2 = CC(1,K,1,1)+CC(1,K,1,3)
48 TI4 = CC(1,K,1,4)-CC(1,K,1,2)
49 TR3 = CC(1,K,1,2)+CC(1,K,1,4)
50 CH(1,K,1,1) = SN*(TR2+TR3)
51 CH(1,K,3,1) = SN*(TR2-TR3)
52 CH(2,K,1,1) = SN*(TI2+TI3)
53 CH(2,K,3,1) = SN*(TI2-TI3)
54 CH(1,K,2,1) = SN*(TR1+TR4)
55 CH(1,K,4,1) = SN*(TR1-TR4)
56 CH(2,K,2,1) = SN*(TI1+TI4)
57 CH(2,K,4,1) = SN*(TI1-TI4)
58 107 END DO
59 RETURN
60 102 DO 103 K=1,L1
61 TI1 = CC(2,K,1,1)-CC(2,K,1,3)
62 TI2 = CC(2,K,1,1)+CC(2,K,1,3)
63 TR4 = CC(2,K,1,2)-CC(2,K,1,4)
64 TI3 = CC(2,K,1,2)+CC(2,K,1,4)
65 TR1 = CC(1,K,1,1)-CC(1,K,1,3)
66 TR2 = CC(1,K,1,1)+CC(1,K,1,3)
67 TI4 = CC(1,K,1,4)-CC(1,K,1,2)
68 TR3 = CC(1,K,1,2)+CC(1,K,1,4)
69 CH(1,K,1,1) = TR2+TR3
70 CH(1,K,3,1) = TR2-TR3
71 CH(2,K,1,1) = TI2+TI3
72 CH(2,K,3,1) = TI2-TI3
73 CH(1,K,2,1) = TR1+TR4
74 CH(1,K,4,1) = TR1-TR4
75 CH(2,K,2,1) = TI1+TI4
76 CH(2,K,4,1) = TI1-TI4
77 103 END DO
78 DO 105 I=2,IDO
79 DO 104 K=1,L1
80 TI1 = CC(2,K,I,1)-CC(2,K,I,3)
81 TI2 = CC(2,K,I,1)+CC(2,K,I,3)
82 TI3 = CC(2,K,I,2)+CC(2,K,I,4)
83 TR4 = CC(2,K,I,2)-CC(2,K,I,4)
84 TR1 = CC(1,K,I,1)-CC(1,K,I,3)
85 TR2 = CC(1,K,I,1)+CC(1,K,I,3)
86 TI4 = CC(1,K,I,4)-CC(1,K,I,2)
87 TR3 = CC(1,K,I,2)+CC(1,K,I,4)
88 CH(1,K,1,I) = TR2+TR3
89 CR3 = TR2-TR3
90 CH(2,K,1,I) = TI2+TI3
91 CI3 = TI2-TI3
92 CR2 = TR1+TR4
93 CR4 = TR1-TR4
94 CI2 = TI1+TI4
95 CI4 = TI1-TI4
96 CH(1,K,2,I) = WA(I,1,1)*CR2+WA(I,1,2)*CI2
97 CH(2,K,2,I) = WA(I,1,1)*CI2-WA(I,1,2)*CR2
98 CH(1,K,3,I) = WA(I,2,1)*CR3+WA(I,2,2)*CI3
99 CH(2,K,3,I) = WA(I,2,1)*CI3-WA(I,2,2)*CR3
100 CH(1,K,4,I) = WA(I,3,1)*CR4+WA(I,3,2)*CI4
101 CH(2,K,4,I) = WA(I,3,1)*CI4-WA(I,3,2)*CR4
102 104 CONTINUE
103 105 END DO
104 RETURN
105 END