00001 subroutine zpassb3 (ido,l1,cc,ch,wa1,wa2)
00002 implicit double precision (a-h,o-z)
00003 dimension cc(ido,3,l1) ,ch(ido,l1,3) ,
00004 1 wa1(1) ,wa2(1)
00005 data taur,taui /-.5,.866025403784439d0/
00006 if (ido .ne. 2) go to 102
00007 do 101 k=1,l1
00008 tr2 = cc(1,2,k)+cc(1,3,k)
00009 cr2 = cc(1,1,k)+taur*tr2
00010 ch(1,k,1) = cc(1,1,k)+tr2
00011 ti2 = cc(2,2,k)+cc(2,3,k)
00012 ci2 = cc(2,1,k)+taur*ti2
00013 ch(2,k,1) = cc(2,1,k)+ti2
00014 cr3 = taui*(cc(1,2,k)-cc(1,3,k))
00015 ci3 = taui*(cc(2,2,k)-cc(2,3,k))
00016 ch(1,k,2) = cr2-ci3
00017 ch(1,k,3) = cr2+ci3
00018 ch(2,k,2) = ci2+cr3
00019 ch(2,k,3) = ci2-cr3
00020 101 continue
00021 return
00022 102 do 104 k=1,l1
00023 do 103 i=2,ido,2
00024 tr2 = cc(i-1,2,k)+cc(i-1,3,k)
00025 cr2 = cc(i-1,1,k)+taur*tr2
00026 ch(i-1,k,1) = cc(i-1,1,k)+tr2
00027 ti2 = cc(i,2,k)+cc(i,3,k)
00028 ci2 = cc(i,1,k)+taur*ti2
00029 ch(i,k,1) = cc(i,1,k)+ti2
00030 cr3 = taui*(cc(i-1,2,k)-cc(i-1,3,k))
00031 ci3 = taui*(cc(i,2,k)-cc(i,3,k))
00032 dr2 = cr2-ci3
00033 dr3 = cr2+ci3
00034 di2 = ci2+cr3
00035 di3 = ci2-cr3
00036 ch(i,k,2) = wa1(i-1)*di2+wa1(i)*dr2
00037 ch(i-1,k,2) = wa1(i-1)*dr2-wa1(i)*di2
00038 ch(i,k,3) = wa2(i-1)*di3+wa2(i)*dr3
00039 ch(i-1,k,3) = wa2(i-1)*dr3-wa2(i)*di3
00040 103 continue
00041 104 continue
00042 return
00043 end
1.7.1
