********>Bugfix for ew_fft.f in AMBER 5.0 sander
Author: Mike Crowley
Date: 11 Feb 98

Programs: sander

Severity: pretty bad for some parallel

In most parallel compilations, the unfixed ew_fft.f will
include calls to both the serial  3Dfft and the
parallel 3D-FFT. THis may go undetected, but will usually cause
error messages, incorrect results and program crash.



*** ew_fft.f_50withbug	Fri Sep 19 10:37:38 1997
--- ew_fft.f        	Thu Feb 12 12:14:59 1998
***************
*** 108,113 ****
--- 108,114 ----
        nfftdim3 = nfft3
        n = nfft3/2
        if ( nfft3 .eq. 2*n )nfftdim3 = nfft3+1
+ #ifndef MPI
  #ifdef FUJFFT
        nfftable = 0
        nffwork = 2*nfftmax
***************
*** 132,138 ****
        sizfftab = nfftable
        sizffwrk  = nffwork
  #endif
! #ifdef MPI
        nt0=numtasks
        numtasks=num_recip
  # ifdef CRAY_1DFFT
--- 133,145 ----
        sizfftab = nfftable
        sizffwrk  = nffwork
  #endif
! #ifdef PUBFFT
!       nfftable = 4*nfftmax + 15
!       nffwork = nfftmax
!       sizfftab = 3*nfftable
!       sizffwrk  = 2*nfftmax
! #endif
! #else /*  MPI  */
        nt0=numtasks
        numtasks=num_recip
  # ifdef CRAY_1DFFT
***************
*** 185,196 ****
  #endif
        numtasks=nt0
  #endif /* MPI */
- #ifdef PUBFFT
-       nfftable = 4*nfftmax + 15
-       nffwork = nfftmax
-       sizfftab = 3*nfftable
-       sizffwrk  = 2*nfftmax
- #endif
        return
        end
  
--- 192,197 ----
***************
*** 393,398 ****
--- 394,400 ----
  
        isign = 1
  
+ #ifndef MPI
  #ifdef SGIFFT
        call ZFFT3D(isign,nfft1,nfft2,nfft3,array,
       $   nfftdim1,nfftdim2,fftable)
***************
*** 411,417 ****
       $   nfftdim1,nfftdim2,fftable,nfftable,ffwork,nffwork)
  #endif
  
! #ifdef MPI
        scale = 1.d0
  c      scale = 1./float(nfft1*nfft2*nfft3)
        call fft3d_zxy(isign,nfft1,nfft2,nfft3,scale,array,
--- 413,419 ----
       $   nfftdim1,nfftdim2,fftable,nfftable,ffwork,nffwork)
  #endif
  
! #else  /* MPI  */
        scale = 1.d0
  c      scale = 1./float(nfft1*nfft2*nfft3)
        call fft3d_zxy(isign,nfft1,nfft2,nfft3,scale,array,
***************
*** 452,461 ****
  c nothing happens here for FUJFFT...
  #endif
  
! #ifdef SGIFFT
        call ZFFT3DI(nfft1,nfft2,nfft3,fftable)
! #endif
! #ifdef CRAYFFT
        isign = 0
        inc1 = 1
        inc2 = NFFTDIM1
--- 454,464 ----
  c nothing happens here for FUJFFT...
  #endif
  
! #ifndef MPI
! # ifdef SGIFFT
        call ZFFT3DI(nfft1,nfft2,nfft3,fftable)
! # endif
! # ifdef CRAYFFT
        isign = 0
        inc1 = 1
        inc2 = NFFTDIM1
***************
*** 464,475 ****
        call CFFT3D(isign,nfft1,nfft2,nfft3,scale,array,
       $      inc1,inc2,inc3,array,inc1,inc2,inc3,fftable,nfftable,
       $      ffwork,nffwork)
! #endif
! #ifdef PUBFFT
        call pubz3di(nfft1,nfft2,nfft3,fftable,nfftable)
! #endif
  
! #ifdef MPI
        isign = 0
        scale = 1.d0
  
--- 467,478 ----
        call CFFT3D(isign,nfft1,nfft2,nfft3,scale,array,
       $      inc1,inc2,inc3,array,inc1,inc2,inc3,fftable,nfftable,
       $      ffwork,nffwork)
! # endif
! # ifdef PUBFFT
        call pubz3di(nfft1,nfft2,nfft3,fftable,nfftable)
! # endif
  
! #else  /*  MPI  */
        isign = 0
        scale = 1.d0
  
***************
*** 1405,1411 ****
  #  endif
  
  
! #endif
  
  
  #ifdef PUBFFT
--- 1408,1414 ----
  #  endif
  
  
! #endif /*  MPI  */
  
  
  #ifdef PUBFFT