1 subroutine z1f3kb ( ido, l1, na, cc, in1, ch, in2, wa )
3 !*****************************************************************************80
5 !! Z1F3KB is an FFTPACK5 auxiliary routine.
15 ! Original complex single precision by Paul Swarztrauber, Richard Valent.
16 ! Complex double precision version by John Burkardt.
21 ! Vectorizing the Fast Fourier Transforms,
22 ! in Parallel Computations,
23 ! edited by G. Rodrigue,
24 ! Academic Press, 1982.
27 ! Fast Fourier Transform Algorithms for Vector Computers,
28 ! Parallel Computing, pages 45-63, 1984.
34 integer ( kind = 4 ) ido
35 integer ( kind = 4 ) in1
36 integer ( kind = 4 ) in2
37 integer ( kind = 4 ) l1
39 real ( kind = 8 ) cc(in1,l1,ido,3)
40 real ( kind = 8 ) ch(in2,l1,3,ido)
49 integer ( kind = 4 ) i
50 integer ( kind = 4 ) k
51 integer ( kind = 4 ) na
52 real ( kind = 8 ), parameter :: taui = 0.866025403784439D+00
53 real ( kind = 8 ), parameter :: taur = -0.5D+00
56 real ( kind = 8 ) wa(ido,2,2)
58 if ( 1 < ido .or. na == 1 ) then
62 tr2 = cc(1,k,1,2)+cc(1,k,1,3)
63 cr2 = cc(1,k,1,1)+taur*tr2
64 ch(1,k,1,1) = cc(1,k,1,1)+tr2
65 ti2 = cc(2,k,1,2)+cc(2,k,1,3)
66 ci2 = cc(2,k,1,1)+taur*ti2
67 ch(2,k,1,1) = cc(2,k,1,1)+ti2
68 cr3 = taui*(cc(1,k,1,2)-cc(1,k,1,3))
69 ci3 = taui*(cc(2,k,1,2)-cc(2,k,1,3))
71 ch(1,k,2,1) = cr2 - ci3
72 ch(1,k,3,1) = cr2 + ci3
73 ch(2,k,2,1) = ci2 + cr3
74 ch(2,k,3,1) = ci2 - cr3
80 tr2 = cc(1,k,i,2)+cc(1,k,i,3)
81 cr2 = cc(1,k,i,1)+taur*tr2
82 ch(1,k,1,i) = cc(1,k,i,1)+tr2
83 ti2 = cc(2,k,i,2)+cc(2,k,i,3)
84 ci2 = cc(2,k,i,1)+taur*ti2
85 ch(2,k,1,i) = cc(2,k,i,1)+ti2
86 cr3 = taui*(cc(1,k,i,2)-cc(1,k,i,3))
87 ci3 = taui*(cc(2,k,i,2)-cc(2,k,i,3))
94 ch(2,k,2,i) = wa(i,1,1) * di2 + wa(i,1,2) * dr2
95 ch(1,k,2,i) = wa(i,1,1) * dr2 - wa(i,1,2) * di2
96 ch(2,k,3,i) = wa(i,2,1) * di3 + wa(i,2,2) * dr3
97 ch(1,k,3,i) = wa(i,2,1) * dr3 - wa(i,2,2) * di3
106 tr2 = cc(1,k,1,2)+cc(1,k,1,3)
107 cr2 = cc(1,k,1,1)+taur*tr2
108 cc(1,k,1,1) = cc(1,k,1,1)+tr2
109 ti2 = cc(2,k,1,2)+cc(2,k,1,3)
110 ci2 = cc(2,k,1,1)+taur*ti2
111 cc(2,k,1,1) = cc(2,k,1,1)+ti2
112 cr3 = taui*(cc(1,k,1,2)-cc(1,k,1,3))
113 ci3 = taui*(cc(2,k,1,2)-cc(2,k,1,3))
115 cc(1,k,1,2) = cr2 - ci3
116 cc(1,k,1,3) = cr2 + ci3
117 cc(2,k,1,2) = ci2 + cr3
118 cc(2,k,1,3) = ci2 - cr3