00001 subroutine passb2 (ido,l1,cc,ch,wa1)
00002 dimension cc(ido,2,l1) ,ch(ido,l1,2) ,
00003 1 wa1(1)
00004 if (ido .gt. 2) go to 102
00005 do 101 k=1,l1
00006 ch(1,k,1) = cc(1,1,k)+cc(1,2,k)
00007 ch(1,k,2) = cc(1,1,k)-cc(1,2,k)
00008 ch(2,k,1) = cc(2,1,k)+cc(2,2,k)
00009 ch(2,k,2) = cc(2,1,k)-cc(2,2,k)
00010 101 continue
00011 return
00012 102 do 104 k=1,l1
00013 do 103 i=2,ido,2
00014 ch(i-1,k,1) = cc(i-1,1,k)+cc(i-1,2,k)
00015 tr2 = cc(i-1,1,k)-cc(i-1,2,k)
00016 ch(i,k,1) = cc(i,1,k)+cc(i,2,k)
00017 ti2 = cc(i,1,k)-cc(i,2,k)
00018 ch(i,k,2) = wa1(i-1)*ti2+wa1(i)*tr2
00019 ch(i-1,k,2) = wa1(i-1)*tr2-wa1(i)*ti2
00020 103 continue
00021 104 continue
00022 return
00023 end
1.7.1
