TABLE OF CONTENTS

ABINIT/m_pawfgr [ Modules ]

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NAME

  m_pawfgr

FUNCTION

  This module contains the definition of the pawfgr_type structured datatype,
  as well as related functions and methods.
  pawfgr_type variables define Fine rectangular GRid parameters and related data.

COPYRIGHT

 Copyright (C) 2013-2024 ABINIT group (MT, FJ)
 This file is distributed under the terms of the
 GNU General Public License, see ~abinit/COPYING
 or http://www.gnu.org/copyleft/gpl.txt .

INPUTS

OUTPUT

NOTES

  * Routines tagged with "@type_name" are strongly connected to the definition of the data type.
    Strongly connected means that the proper functioning of the implementation relies on the
    assumption that the tagged procedure is consistent with the type declaration.
    Every time a developer changes the structure "type_name" adding new entries, he/she has to make sure
    that all the strongly connected routines are changed accordingly to accommodate the modification of the data type
    Typical examples of strongly connected routines are creation, destruction or reset methods.

SOURCE

30 #if defined HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33 
34 #include "abi_common.h"
35 
36 MODULE m_pawfgr
37 
38  use defs_basis
39  use m_errors
40  use m_abicore
41  use m_xmpi
42  use m_dtset
43 
44  use m_kg,       only : getcut
45 
46  implicit none
47 
48  private
49 
50 !public procedures.
51  public :: pawfgr_init
52  public :: pawfgr_destroy
53  public :: pawfgr_nullify
54  public :: indgrid

m_paw_ij/pawfgr_nullify [ Functions ]

[ Top ] [ m_paw_ij ] [ Functions ]

NAME

  pawfgr_nullify

FUNCTION

  Nullify pointers and flags in a pawfgr structure

SIDE EFFECTS

  Pawfgr<type(pawfgr_type)>=Fine GRid parameters and related data. Nullified in output

SOURCE

324 subroutine pawfgr_nullify(Pawfgr)
325 
326 !Arguments ------------------------------------
327 !arrays
328  type(Pawfgr_type),intent(inout) :: Pawfgr
329 
330 !Local variables-------------------------------
331 
332 ! *************************************************************************
333 
334  !@Pawfgr_type
335 
336   nullify(Pawfgr%coatofin)
337   nullify(Pawfgr%fintocoa)
338 
339   Pawfgr%usefinegrid=0
340 
341 end subroutine pawfgr_nullify

m_pawfgr/indgrid [ Functions ]

[ Top ] [ m_pawfgr ] [ Functions ]

NAME

 indgrid

FUNCTION

 Calculate the correspondance between the coarse grid and the fine grid

INPUTS

 nfftc=total number of FFt grid=n1*n2*n3 for the coarse grid
 nfftf=total number of FFt grid=n1*n2*n3 for the fine grid
 ngfftc(18)=contain all needed information about 3D FFT, for the coarse grid,
        see ~abinit/doc/variables/vargs.htm#ngfft
 ngfftf(18)=contain all needed information about 3D FFT, for the fine grid,
        see ~abinit/doc/variables/vargs.htm#ngfft

OUTPUT

 coatofin(nfftc)= index of the points of the coarse grid on the fine grid
 fintocoa(nfftf)=index of the points of the fine grid on the
   coarse grid (=0 if the point of the fine grid does not belong to
   the coarse grid).

SOURCE

370 subroutine indgrid(coatofin,fintocoa,nfftc,nfftf,ngfftc,ngfftf)
371 
372 !Arguments ------------------------------------
373 !scalars
374  integer,intent(in) :: nfftc,nfftf
375 !arrays
376  integer,intent(in) :: ngfftc(18),ngfftf(18)
377  integer,intent(out) :: coatofin(nfftc),fintocoa(nfftf)
378 
379 !Local variables-------------------------------
380 !scalars
381  integer :: i1,i2,i3,if1,if2,if3,ii,ing,n1c,n1f,n2c,n2f,n3c,n3f,narg1,narg2
382 !arrays
383  integer :: id(3)
384  integer,allocatable :: gc(:,:),gf(:,:)
385  character(len=500) :: msg
386 
387 ! *************************************************************************
388 
389  DBG_ENTER("COLL")
390 
391  n1c=ngfftc(1);n2c=ngfftc(2);n3c=ngfftc(3)
392  n1f=ngfftf(1);n2f=ngfftf(2);n3f=ngfftf(3)
393 
394  ABI_MALLOC(gc,(3,max(n1c,n2c,n3c)))
395  do ii=1,3
396    id(ii)=ngfftc(ii)/2+2
397    do ing=1,ngfftc(ii)
398      gc(ii,ing)=ing-(ing/id(ii))*ngfftc(ii)-1
399    end do
400  end do
401 
402  ABI_MALLOC(gf,(3,max(n1f,n2f,n3f)))
403  do ii=1,3
404    id(ii)=ngfftf(ii)/2+2
405    do ing=1,ngfftf(ii)
406      gf(ii,ing)=ing-(ing/id(ii))*ngfftf(ii)-1
407    end do
408  end do
409 
410  coatofin=0;fintocoa=0
411  do i1=1,n1c
412    do if1=1,n1f
413      if(gc(1,i1)==gf(1,if1)) then
414        do i2=1,n2c
415          do if2=1,n2f
416            if(gc(2,i2)==gf(2,if2)) then
417              do i3=1,n3c
418                do if3=1,n3f
419                  if(gc(3,i3)==gf(3,if3)) then
420                    narg1=i1+n1c*(i2-1+n2c*(i3-1))
421                    narg2=if1+n1f*(if2-1+n2f*(if3-1))
422                    coatofin(narg1)=narg2
423                    fintocoa(narg2)=narg1
424                    exit
425                  end if
426                end do
427              end do
428              exit ! To avoid N_fine * N_coarse scaling
429            end if
430          end do
431        end do
432        exit ! To avoid N_fine * N_coarse scaling
433      end if
434    end do
435  end do
436 
437 !Check coatofin to make sure there are no zeros!
438  do ii=1,ubound(coatofin,1)
439    if (coatofin(ii)==0) then
440      msg = 'A zero was found in coatofin. Check that the fine FFT mesh is finer in each dimension than the coarse FFT mesh.'
441      ABI_ERROR(msg)
442    end if
443  end do
444 
445  ABI_FREE(gf)
446  ABI_FREE(gc)
447 
448  DBG_EXIT("COLL")
449 
450 end subroutine indgrid

m_pawfgr/pawfgr_destroy [ Functions ]

[ Top ] [ m_pawfgr ] [ Functions ]

NAME

  pawfgr_destroy

FUNCTION

  Deallocate pointers and nullify flags in a pawfgr structure

SIDE EFFECTS

  pawfgr<type(pawfgr_type)>= Fine GRid parameters and related data

SOURCE

282 subroutine pawfgr_destroy(Pawfgr)
283 
284 !Arguments ------------------------------------
285 !arrays
286  type(Pawfgr_type),intent(inout) :: Pawfgr
287 
288 !Local variables-------------------------------
289 
290 ! *************************************************************************
291 
292  DBG_ENTER("COLL")
293 
294 !@Pawfgr_type
295 
296  if (associated(Pawfgr%coatofin))  then
297    ABI_FREE(Pawfgr%coatofin)
298  end if
299  if (associated(Pawfgr%fintocoa))  then
300    ABI_FREE(Pawfgr%fintocoa)
301  end if
302 
303  Pawfgr%usefinegrid=0
304 
305  DBG_EXIT("COLL")
306 
307 end subroutine pawfgr_destroy

m_pawfgr/pawfgr_init [ Functions ]

[ Top ] [ m_pawfgr ] [ Functions ]

NAME

 pawfgr_init

FUNCTION

  Initialize a pawfgr_type datatype, reporting also info on the mesh
  according to the method used (norm-conserving PSP or PAW)

INPUTS

  k0(3)=input k vector for k+G sphere
  Dtset <type(dataset_type)>=all input variables for this dataset
   %dilatmx
   %usepaw
   %usewvl
   %natom
   %ngfft
   %ngfftdg
   %nfft
   %mgfft
   %mgfftdg
   %dilatmx
   %pawecutdg
   %ecut
  gmet(3,3)=reciprocal space metric (bohr^-2)

OUTPUT

  ecut_eff=effective energy cutoff (hartree) for coarse planewave basis sphere
  ecutdg_eff=effective energy cutoff (hartree) for dense planewave basis sphere
  gsqcutc_eff=(PAW) Fourier cutoff on G^2 for "large sphere" of radius double for the coarse FFT grid
  nfftf=(effective) number of FFT grid points (for this proc), for dense FFT mesh
  mgfftf=maximum size of 1D FFTs, for dense FFT mesh
  ngfftc(18),ngfftf(18)=contain all needed information about 3D FFT, for coarse and dense FFT mesh, resp.
                        see ~abinit/doc/variables/vargs.htm#ngfft
  Pawfgr<pawfgr_type>=For PAW, Fine rectangular GRid parameters and related data

SOURCE

158 subroutine pawfgr_init(Pawfgr,Dtset,mgfftf,nfftf,ecut_eff,ecutdg_eff,ngfftc,ngfftf,&
159 &                      gsqcutc_eff,gsqcutf_eff,gmet,k0) ! optional
160 
161 !Arguments ------------------------------------
162 !scalars
163  integer,intent(out) :: nfftf,mgfftf
164  real(dp),intent(out) :: ecut_eff,ecutdg_eff
165  real(dp),intent(out),optional :: gsqcutf_eff,gsqcutc_eff
166  type(dataset_type),intent(in) :: Dtset
167  type(Pawfgr_type),intent(out) :: Pawfgr
168 !arrays
169  real(dp),intent(in),optional :: gmet(3,3)
170  integer,intent(out) :: ngfftc(18),ngfftf(18)
171  real(dp),intent(in),optional :: k0(3)
172 
173 !Local variables-------------------------------
174  integer :: ii,nfftc_tot,nfftf_tot
175  real(dp) :: boxcut,boxcutc
176  character(len=500) :: msg
177 
178 !************************************************************************
179 
180  DBG_ENTER("COLL")
181 
182  !@Pawfgr_type
183  if ((present(gsqcutc_eff).or.present(gsqcutf_eff)).and.&
184     ((.not.present(gmet)).or.(.not.present(k0)))) then
185    ABI_BUG('To compute gsqcut[c,f]_eff, both k0 and gmet must be present as argument !')
186  end if
187 
188  ngfftc(:)=Dtset%ngfft(:)
189 
190  SELECT CASE (Dtset%usepaw)
191 
192  CASE (0)
193   ! === Norm-conserving pseudopotentials ===
194   nfftf=Dtset%nfft ; mgfftf=Dtset%mgfft ; ngfftf(:)=Dtset%ngfft(:)
195   Pawfgr%usefinegrid=0
196   ABI_MALLOC(Pawfgr%coatofin,(0))
197   ABI_MALLOC(Pawfgr%fintocoa,(0))
198   ecut_eff  =Dtset%ecut*Dtset%dilatmx**2
199   ecutdg_eff=ecut_eff
200 
201  CASE (1)
202   ! == PAW calculation ===
203   if (any(Dtset%ngfftdg(1:3)/=Dtset%ngfft(1:3)) .and. Dtset%usewvl==0) then
204     ! Use fine FFT grid generated according to pawecutdg.
205     nfftf=Dtset%nfftdg ; mgfftf=Dtset%mgfftdg ; ngfftf(:)=Dtset%ngfftdg(:)
206     nfftc_tot =ngfftc(1)*ngfftc(2)*ngfftc(3)
207     nfftf_tot =ngfftf(1)*ngfftf(2)*ngfftf(3)
208     Pawfgr%usefinegrid=1
209     ABI_MALLOC(Pawfgr%coatofin,(nfftc_tot))
210     ABI_MALLOC(Pawfgr%fintocoa,(nfftf_tot))
211     call indgrid(Pawfgr%coatofin,Pawfgr%fintocoa,nfftc_tot,nfftf_tot,ngfftc,ngfftf)
212 
213   else
214     ! Do not use fine FFT mesh. Simple transfer that can be done in parallel with only local info.
215     nfftf=Dtset%nfft ; mgfftf=Dtset%mgfft ; ngfftf(:)=Dtset%ngfft(:)
216     Pawfgr%usefinegrid=0
217     ABI_MALLOC(Pawfgr%coatofin,(Dtset%nfft))
218     ABI_MALLOC(Pawfgr%fintocoa,(Dtset%nfft))
219     do ii=1,Dtset%nfft
220       Pawfgr%coatofin(ii)=ii ; Pawfgr%fintocoa(ii)=ii
221     end do
222   end if
223   ecutdg_eff=Dtset%pawecutdg*Dtset%dilatmx**2
224   ecut_eff  =Dtset%ecut*Dtset%dilatmx**2
225 
226  CASE DEFAULT
227   write(msg,'(a,i4)')' Wrong value of usepaw: ',Dtset%usepaw
228   ABI_BUG(msg)
229  END SELECT
230 
231 ! Store useful dimensions in Pawfgr
232  Pawfgr%nfftc=Dtset%nfft ; Pawfgr%mgfftc=Dtset%mgfft ; Pawfgr%ngfftc(:)=Dtset%ngfft(:)
233  Pawfgr%nfft=nfftf       ; Pawfgr%mgfft=mgfftf       ; Pawfgr%ngfft (:)=ngfftf(:)
234 
235  ! Get boxcut for given gmet, ngfft, and ecut (center at k0) ===
236  ! boxcut=ratio of basis sphere diameter to fft box side
237  boxcut=-one
238  if (Dtset%usepaw==1) then
239    if (present(gsqcutc_eff)) then
240      write(msg,'(2a)')ch10,' Coarse grid specifications (used for wave-functions):'
241      call wrtout(std_out,msg)
242      call getcut(boxcutc,ecut_eff,gmet,gsqcutc_eff,Dtset%iboxcut,std_out,k0,ngfftc)
243    end if
244    if (present(gsqcutf_eff)) then
245      write(msg,'(2a)')ch10,' Fine grid specifications (used for densities):'
246      call wrtout(std_out,msg)
247      call getcut(boxcut,ecutdg_eff,gmet,gsqcutf_eff,Dtset%iboxcut,std_out,k0,ngfftf)
248    end if
249  else if (present(gsqcutc_eff)) then
250    call getcut(boxcut,ecut_eff,gmet,gsqcutc_eff,Dtset%iboxcut,std_out,k0,ngfftc)
251    gsqcutf_eff=gsqcutc_eff
252  end if
253 
254  ! Check that boxcut>=2 if intxc=1; otherwise intxc must be set=0.
255  if (boxcut>=zero .and. boxcut<two .and. Dtset%intxc==1) then
256    write(msg,'(a,es12.4,5a)')&
257    ' boxcut=',boxcut,' is < 2.0  => intxc must be 0;',ch10,&
258    ' Need larger ngfft to use intxc=1.',ch10,&
259    ' Action: you could increase ngfft, or decrease ecut, or put intxc=0.'
260    ABI_ERROR(msg)
261  end if
262 
263  DBG_EXIT("COLL")
264 
265 end subroutine pawfgr_init

m_pawfgr/pawfgr_type [ Types ]

[ Top ] [ m_pawfgr ] [ Types ]

NAME

 pawfgr_type

FUNCTION

 For PAW, Fine GRid parameters and related data

SOURCE

 69  type,public :: pawfgr_type
 70 
 71 ! WARNING : if you modify this datatype, please check whether there might be creation/destruction/copy routines,
 72 ! declared in another part of ABINIT, that might need to take into account your modification.
 73 
 74 !Integer scalars
 75 
 76   integer :: mgfft, nfft
 77    ! Values of mffft and nfft for the fine grid:
 78    !   mgfft= max(ngfft(i)) [max. size of 1D FFT grid]
 79    !   nfft=ngfft1*ngfft2*ngfft3 [number of pts in the FFT box]
 80 
 81   integer :: mgfftc, nfftc
 82    ! Values of mffft and nfft for the COARSE grid:
 83    !   mgfftc= max(ngfftc(i)) [max. size of 1D FFT grid]
 84    !   nfftc=ngfftc1*ngfftc2*ngfftc3 [number of pts in the FFT box]
 85 
 86   integer :: usefinegrid
 87    ! Flag: =1 if a double-grid is used to convert spherical data
 88    !       to Fourier grid. =0 otherwise
 89 
 90 !Integer arrays
 91 
 92   ! MG TODO: Replace with allocatable
 93   integer, pointer :: coatofin(:)
 94    ! coatofin(nfftc)
 95    ! Index of the points of the coarse grid on the fine grid
 96 
 97   integer, pointer :: fintocoa(:)
 98    ! fintocoa(nfft)
 99    ! Index of the points of the fine grid on the coarse grid
100    !  (=0 if the point of the fine grid does not belong to the coarse grid)
101 
102   integer :: ngfft(18)
103    ! ngfft(1:18)=integer array with FFT box dimensions and other
104    ! information on FFTs, for the fine rectangular grid
105 
106   integer :: ngfftc(18)
107    ! ngfft(1:18)=integer array with FFT box dimensions and other
108    ! information on FFTs, for the COARSE rectangular grid
109 
110  end type pawfgr_type