subroutine radf3(Ido,l1,Cc,Ch,Wa1,Wa2)
use fftpack_kind
implicit none
real(rk) :: Cc , Ch , ci2 , cr2 , di2 , di3 , dr2 , dr3 , &
ti2 , ti3 , tr2 , tr3 , Wa1 , Wa2
integer :: i , ic , Ido , idp2 , k , l1
dimension Ch(Ido,3,l1) , Cc(Ido,l1,3) , Wa1(*) , Wa2(*)
real(rk),parameter :: taur = -0.5_rk
! note: original comment said this was -SQRT(3)/2 but value was 0.86602540378443864676d0
real(rk),parameter :: taui = sqrt(3.0_rk) / 2.0_rk
do k = 1 , l1
cr2 = Cc(1,k,2) + Cc(1,k,3)
Ch(1,1,k) = Cc(1,k,1) + cr2
Ch(1,3,k) = taui*(Cc(1,k,3)-Cc(1,k,2))
Ch(Ido,2,k) = Cc(1,k,1) + taur*cr2
enddo
if ( Ido==1 ) return
idp2 = Ido + 2
do k = 1 , l1
do i = 3 , Ido , 2
ic = idp2 - i
dr2 = Wa1(i-2)*Cc(i-1,k,2) + Wa1(i-1)*Cc(i,k,2)
di2 = Wa1(i-2)*Cc(i,k,2) - Wa1(i-1)*Cc(i-1,k,2)
dr3 = Wa2(i-2)*Cc(i-1,k,3) + Wa2(i-1)*Cc(i,k,3)
di3 = Wa2(i-2)*Cc(i,k,3) - Wa2(i-1)*Cc(i-1,k,3)
cr2 = dr2 + dr3
ci2 = di2 + di3
Ch(i-1,1,k) = Cc(i-1,k,1) + cr2
Ch(i,1,k) = Cc(i,k,1) + ci2
tr2 = Cc(i-1,k,1) + taur*cr2
ti2 = Cc(i,k,1) + taur*ci2
tr3 = taui*(di2-di3)
ti3 = taui*(dr3-dr2)
Ch(i-1,3,k) = tr2 + tr3
Ch(ic-1,2,k) = tr2 - tr3
Ch(i,3,k) = ti2 + ti3
Ch(ic,2,k) = ti3 - ti2
enddo
enddo
end subroutine radf3
