subroutine sradb2 (ido,l1,cc,ch,wa1) real cc(ido,2,l1), ch(ido,l1,2), wa1(1), ti2, tr2 c do 101 k=1,l1 ch(1,k,1) = cc(1,1,k)+cc(ido,2,k) ch(1,k,2) = cc(1,1,k)-cc(ido,2,k) 101 continue c if (ido-2) 107,105,102 102 idp2 = ido+2 do 104 k=1,l1 do 103 i=3,ido,2 ic = idp2-i ch(i-1,k,1) = cc(i-1,1,k)+cc(ic-1,2,k) tr2 = cc(i-1,1,k)-cc(ic-1,2,k) ch(i,k,1) = cc(i,1,k)-cc(ic,2,k) ti2 = cc(i,1,k)+cc(ic,2,k) ch(i-1,k,2) = wa1(i-2)*tr2-wa1(i-1)*ti2 ch(i,k,2) = wa1(i-2)*ti2+wa1(i-1)*tr2 103 continue 104 continue c if (mod(ido,2) .eq. 1) return 105 do 106 k=1,l1 ch(ido,k,1) = cc(ido,1,k)+cc(ido,1,k) ch(ido,k,2) = -(cc(1,2,k)+cc(1,2,k)) 106 continue c 107 return end