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comparison libcruft/fftpack/zpassf3.f @ 7789:82be108cc558

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First attempt at single precision tyeps * * * corrections to qrupdate single precision routines * * * prefer demotion to single over promotion to double * * * Add single precision support to log2 function * * * Trivial PROJECT file update * * * Cache optimized hermitian/transpose methods * * * Add tests for tranpose/hermitian and ChangeLog entry for new transpose code
author David Bateman <dbateman@free.fr>
date Sun, 27 Apr 2008 22:34:17 +0200
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7788:45f5faba05a2 7789:82be108cc558
1 subroutine zpassf3 (ido,l1,cc,ch,wa1,wa2)
2 implicit double precision (a-h,o-z)
3 dimension cc(ido,3,l1) ,ch(ido,l1,3) ,
4 1 wa1(1) ,wa2(1)
5 data taur,taui /-.5d0,-.866025403784439d0/
6 if (ido .ne. 2) go to 102
7 do 101 k=1,l1
8 tr2 = cc(1,2,k)+cc(1,3,k)
9 cr2 = cc(1,1,k)+taur*tr2
10 ch(1,k,1) = cc(1,1,k)+tr2
11 ti2 = cc(2,2,k)+cc(2,3,k)
12 ci2 = cc(2,1,k)+taur*ti2
13 ch(2,k,1) = cc(2,1,k)+ti2
14 cr3 = taui*(cc(1,2,k)-cc(1,3,k))
15 ci3 = taui*(cc(2,2,k)-cc(2,3,k))
16 ch(1,k,2) = cr2-ci3
17 ch(1,k,3) = cr2+ci3
18 ch(2,k,2) = ci2+cr3
19 ch(2,k,3) = ci2-cr3
20 101 continue
21 return
22 102 do 104 k=1,l1
23 do 103 i=2,ido,2
24 tr2 = cc(i-1,2,k)+cc(i-1,3,k)
25 cr2 = cc(i-1,1,k)+taur*tr2
26 ch(i-1,k,1) = cc(i-1,1,k)+tr2
27 ti2 = cc(i,2,k)+cc(i,3,k)
28 ci2 = cc(i,1,k)+taur*ti2
29 ch(i,k,1) = cc(i,1,k)+ti2
30 cr3 = taui*(cc(i-1,2,k)-cc(i-1,3,k))
31 ci3 = taui*(cc(i,2,k)-cc(i,3,k))
32 dr2 = cr2-ci3
33 dr3 = cr2+ci3
34 di2 = ci2+cr3
35 di3 = ci2-cr3
36 ch(i,k,2) = wa1(i-1)*di2-wa1(i)*dr2
37 ch(i-1,k,2) = wa1(i-1)*dr2+wa1(i)*di2
38 ch(i,k,3) = wa2(i-1)*di3-wa2(i)*dr3
39 ch(i-1,k,3) = wa2(i-1)*dr3+wa2(i)*di3
40 103 continue
41 104 continue
42 return
43 end