subroutine xspacec(kxac,kxas,kxa1)
c
c Transform a variable from kx space into x space.
c
      implicit none
      include 'itg.par'
      include 'itg.cmn'
      real kxac(lz,mz,nz,nspecz),kxas(lz,mz,nz,nspecz)
      integer l,m,n,ifail,nmodes,index,imode

      complex kxa(nzz,mz*lz),kxa1(nzz,mz*lz)
      real scale,work(4*lz*mz*nzz)
      integer isign,nwork,ntablex

      nwork=4*lz*mz*nzz
c      scale=1./sqrt(float(nalias))
      scale=1.
      ntablex=100+2*nzz
      isign=-1
c
      do n=1,nddp
         do m=1,md
            do l=1,ldb
               imode=l+(m-1)*ldb
               kxa(n,imode)=cmplx(kxac(l,m,n,1),-kxas(l,m,n,1))
            enddo
         enddo
      enddo
c
      do n=nadd+nddp+1,nalias
         do m=1,md
            do l=1,ldb
               imode=l+(m-1)*ldb
               kxa(n,imode)=
     &              cmplx(kxac(l,m,n-nadd,1),-kxas(l,m,n-nadd,1))
            enddo
         enddo
      enddo
c
c     de-alias
c       
      do n=nddp+1,nddp+nadd
         do m=1,md
            do l=1,ldb
               imode=l+(m-1)*ldb
               kxa(n,imode)=0.0
            enddo
         enddo
      enddo

      call xmcfft(isign,nalias,md*ldb,scale,kxa,1,nzz,kxa1,1,nzz,
     &     tablex,ntablex,work,nwork)

      return
      end