Mercurial > octave-nkf
view libcruft/fftpack/zpassf3.f @ 7789:82be108cc558
First attempt at single precision tyeps
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corrections to qrupdate single precision routines
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prefer demotion to single over promotion to double
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Add single precision support to log2 function
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Trivial PROJECT file update
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Cache optimized hermitian/transpose methods
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Add tests for tranpose/hermitian and ChangeLog entry for new transpose code
author | David Bateman <dbateman@free.fr> |
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date | Sun, 27 Apr 2008 22:34:17 +0200 |
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subroutine zpassf3 (ido,l1,cc,ch,wa1,wa2) implicit double precision (a-h,o-z) dimension cc(ido,3,l1) ,ch(ido,l1,3) , 1 wa1(1) ,wa2(1) data taur,taui /-.5d0,-.866025403784439d0/ if (ido .ne. 2) go to 102 do 101 k=1,l1 tr2 = cc(1,2,k)+cc(1,3,k) cr2 = cc(1,1,k)+taur*tr2 ch(1,k,1) = cc(1,1,k)+tr2 ti2 = cc(2,2,k)+cc(2,3,k) ci2 = cc(2,1,k)+taur*ti2 ch(2,k,1) = cc(2,1,k)+ti2 cr3 = taui*(cc(1,2,k)-cc(1,3,k)) ci3 = taui*(cc(2,2,k)-cc(2,3,k)) ch(1,k,2) = cr2-ci3 ch(1,k,3) = cr2+ci3 ch(2,k,2) = ci2+cr3 ch(2,k,3) = ci2-cr3 101 continue return 102 do 104 k=1,l1 do 103 i=2,ido,2 tr2 = cc(i-1,2,k)+cc(i-1,3,k) cr2 = cc(i-1,1,k)+taur*tr2 ch(i-1,k,1) = cc(i-1,1,k)+tr2 ti2 = cc(i,2,k)+cc(i,3,k) ci2 = cc(i,1,k)+taur*ti2 ch(i,k,1) = cc(i,1,k)+ti2 cr3 = taui*(cc(i-1,2,k)-cc(i-1,3,k)) ci3 = taui*(cc(i,2,k)-cc(i,3,k)) dr2 = cr2-ci3 dr3 = cr2+ci3 di2 = ci2+cr3 di3 = ci2-cr3 ch(i,k,2) = wa1(i-1)*di2-wa1(i)*dr2 ch(i-1,k,2) = wa1(i-1)*dr2+wa1(i)*di2 ch(i,k,3) = wa2(i-1)*di3-wa2(i)*dr3 ch(i-1,k,3) = wa2(i-1)*dr3+wa2(i)*di3 103 continue 104 continue return end