subroutine fftcr (hcdat,nhcpts,signex,rltrn,nrlpts,work,lwrk,ierr)
c
      complex         hcdat(nhcpts)
      real            rltrn(nrlpts)          ,work(lwrk)
      dimension       nscrt(1)
c the following call is for gathering statistics on library use at ncar
c      logical q8q4
c      save q8q4
c      data q8q4 /.true./
c      if (q8q4) then
c          call q8qst4('loclib','fft','fftcr','version 08')
c          q8q4 = .false.
c      endif
      ierr = 0
      if (nrlpts .lt. 2) go to 103
      if (nhcpts .ne. nrlpts/2+1) go to 105
      if (lwrk .lt. 4*nrlpts) go to 106
      nc = 2*nrlpts+4
      work(1) = real(hcdat(1))
      work(2) = 0.
      do 101 k=2,nhcpts
         work(2*k-1) = real(hcdat(k))
      nc2 = nc-2*k-1
      work(nc2) = real(hcdat(k))
         work(2*k) = aimag(hcdat(k))
      nc2 = nc-2*k
      work(nc2) = -aimag(hcdat(k))
  101 continue
      isign = signex
      nscrt(1) = nrlpts
      call fourt (work,nscrt,1,isign,1,work(2*nrlpts+1))
      do 102 j=1,nrlpts
         rltrn(j) = work(2*j-1)
  102 continue
      return
  103 if (nrlpts .lt. 1) go to 104
      if (nhcpts .ne. 1) go to 105
      rltrn(1) = real(hcdat(1))
      return
  104 ierr = 101
      call uliber (ierr,25h fftcr   nrlpts is .lt. 1,25)
      return
  105 ierr = 102
      call uliber (ierr,33h fftcr   nhcpts is not nrlpts/2+1,33)
      return
  106 ierr = 103
      call uliber (ierr,55h fftcr   insufficient workspace - lwrk is .lt
     1. 4*nrlpts   ,55)
      return
      end