Line data Source code
1 : !!****m* ABINIT/m_lobpcg
2 : !! NAME
3 : !! m_lobpcg
4 : !!
5 : !! FUNCTION
6 : !! This module provides the procedures used in the LOBPCGWF routine.
7 : !! They permit to hide the complex/real form of the WFs.
8 : !!
9 : !! COPYRIGHT
10 : !! Copyright (C) 2009-2026 ABINIT group (FBottin,CS,FDahm,MT)
11 : !! This file is distributed under the terms of the
12 : !! GNU General Public License, see ~abinit/COPYING
13 : !! or http://www.gnu.org/copyleft/gpl.txt .
14 : !! For the initials of contributors, see ~abinit/doc/developers/contributors.txt.
15 : !!
16 : !! NOTES
17 : !!
18 : !! SOURCE
19 :
20 : #if defined HAVE_CONFIG_H
21 : #include "config.h"
22 : #endif
23 :
24 : #include "abi_common.h"
25 :
26 : MODULE m_lobpcg
27 :
28 : use defs_basis
29 : use m_abicore
30 : use m_errors
31 : use m_wfutils
32 : use m_abi_linalg
33 : use m_cgtools
34 : use m_dtset
35 :
36 : use defs_abitypes, only : mpi_type
37 : use m_time, only : timab
38 :
39 : implicit none
40 :
41 : private
42 :
43 : !public procedures.
44 : public :: xprecon
45 : !!***
46 :
47 : CONTAINS
48 : !----------------------------------------------------------------------
49 :
50 :
51 : !! NAME
52 : !! xprecon
53 : !!
54 : !! FUNCTION
55 : !! precondition $<G|(H-e_{n,k})|C_{n,k}>$
56 : !! for a block of band (band-FFT parallelisation)
57 : !!
58 : !! COPYRIGHT
59 : !! Copyright (C) 1998-2026 ABINIT group (FBottin,CS)
60 : !! this file is distributed under the terms of the
61 : !! gnu general public license, see ~abinit/COPYING
62 : !! or http://www.gnu.org/copyleft/gpl.txt .
63 : !! for the initials of contributors, see ~abinit/doc/developers/contributors.txt .
64 : !!
65 : !! INPUTS
66 : !! blocksize= size of blocks of bands
67 : !! $cg(vectsize,blocksize)=<G|C_{n,k}> for a block of bands$.
68 : !! $eval(blocksize,blocksize)=current block of bands eigenvalues=<C_{n,k}|H|C_{n,k}>$.
69 : !! $ghc(vectsize,blocksize)=<G|H|C_{n,k}> for a block of bands$.
70 : !! iterationnumber=number of iterative minimizations in LOBPCG
71 : !! kinpw(npw)=(modified) kinetic energy for each plane wave (Hartree)
72 : !! mpi_enreg=information about MPI parallelization
73 : !! nspinor=number of spinorial components of the wavefunctions (on current proc)
74 : !! $vect(vectsize,blocksize)=<G|H|C_{n,k}> for a block of bands$.
75 : !! npw=number of planewaves at this k point.
76 : !! optekin= 1 if the kinetic energy used in preconditionning is modified
77 : !! according to Kresse, Furthmuller, PRB 54, 11169 (1996) [[cite:Kresse1996]]
78 : !! 0 otherwise
79 : !! optpcon= 0 the TPA preconditionning matrix does not depend on band
80 : !! 1 the TPA preconditionning matrix (not modified)
81 : !! 2 the TPA preconditionning matrix is independant of iterationnumber
82 : !! vectsize= size of vectors
83 : !!
84 : !! OUTPUT
85 : !! vect(2,npw)=<g|(h-eval)|c_{n,k}>*(polynomial ratio)
86 : !!
87 : !! SOURCE
88 :
89 34551 : subroutine xprecon(cg,eval,blocksize,iterationnumber,kinpw,&
90 34551 : & mpi_enreg,npw,nspinor,optekin,optpcon,pcon,ghc,vect,vectsize,&
91 : & timopt,tim_xprecon) ! optional arguments
92 :
93 : !Arguments ------------------------------------
94 : !scalars
95 : integer,intent(in) :: blocksize,iterationnumber,npw,nspinor,optekin
96 : integer,intent(in) :: optpcon,vectsize
97 : integer, intent(in), optional :: timopt,tim_xprecon
98 : type(mpi_type),intent(in) :: mpi_enreg
99 : !arrays
100 : real(dp),intent(inout) :: cg(vectsize,blocksize),eval(blocksize,blocksize)
101 : real(dp),intent(in) :: kinpw(npw)
102 : real(dp),intent(inout) :: ghc(vectsize,blocksize)
103 : real(dp),intent(inout) :: pcon(npw,blocksize),vect(vectsize,blocksize)
104 :
105 : !Local variables-------------------------------
106 34551 : complex(dp),dimension(:,:),allocatable :: z_cg,z_eval,z_ghc,z_vect
107 : real(dp) :: tsec(2)
108 : ! *********************************************************************
109 :
110 34551 : if (present(tim_xprecon).and.present(timopt)) then
111 34551 : if(abs(timopt)==3) then
112 0 : call timab(tim_xprecon,1,tsec)
113 : end if
114 : end if
115 :
116 34551 : if ( x_cplx == 1 ) then
117 : call cg_precon_block(cg,eval,blocksize,iterationnumber,kinpw,&
118 2079 : & npw,nspinor,mpi_enreg%me_g0,optekin,optpcon,pcon,ghc,vect,vectsize,mpi_enreg%comm_bandspinorfft)
119 : else
120 129888 : ABI_MALLOC(z_cg,(vectsize,blocksize))
121 129888 : ABI_MALLOC(z_eval,(blocksize,blocksize))
122 97416 : ABI_MALLOC(z_ghc,(vectsize,blocksize))
123 97416 : ABI_MALLOC(z_vect,(vectsize,blocksize))
124 :
125 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,cg,1,z_cg,1)
126 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,ghc,1,z_ghc,1)
127 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,vect,1,z_vect,1)
128 32472 : call abi_xcopy(x_cplx*blocksize*blocksize,eval,1,z_eval,1)
129 :
130 : call cg_zprecon_block(z_cg,z_eval,blocksize,iterationnumber,kinpw,&
131 32472 : & npw,nspinor,optekin,optpcon,pcon,z_ghc,z_vect,vectsize,mpi_enreg%comm_bandspinorfft)
132 :
133 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,z_cg,1,cg,1)
134 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,z_ghc,1,ghc,1)
135 32472 : call abi_xcopy(x_cplx*vectsize*blocksize,z_vect,1,vect,1)
136 32472 : call abi_xcopy(x_cplx*blocksize*blocksize,z_eval,1,eval,1)
137 :
138 32472 : ABI_FREE(z_cg)
139 32472 : ABI_FREE(z_eval)
140 32472 : ABI_FREE(z_ghc)
141 32472 : ABI_FREE(z_vect)
142 : endif
143 :
144 34551 : if (present(tim_xprecon).and.present(timopt)) then
145 34551 : if(abs(timopt)==3) then
146 0 : call timab(tim_xprecon,2,tsec)
147 : end if
148 : end if
149 :
150 34551 : end subroutine xprecon
151 : !!***
152 :
153 : !----------------------------------------------------------------------
154 :
155 : END MODULE m_lobpcg
156 : !!***
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