Date: 2022-08-09T09:05:39+00:00

Actual source code: test15f.F
slepc-3.17.2 2022-08-09
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      1: !
      2: !  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3: !  SLEPc - Scalable Library for Eigenvalue Problem Computations
      4: !  Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain
      5: !
      6: !  This file is part of SLEPc.
      7: !  SLEPc is distributed under a 2-clause BSD license (see LICENSE).
      8: !  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      9: !
     10: !  Program usage: mpiexec -n <np> ./test15f [-help] [-n <n>] [all SLEPc options]
     11: !
     12: !  Description: Tests custom monitors from Fortran.
     13: !
     14: !  The command line options are:
     15: !    -n <n>, where <n> = number of grid points = matrix size
     16: !    -my_eps_monitor, activates the custom monitor
     17: !
     18: ! ----------------------------------------------------------------------
     19: !
     20:       program main
     21: #include <slepc/finclude/slepceps.h>
     22:       use slepceps
     23:       implicit none

     25: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     26: !     Declarations
     27: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     28: !
     29: !  Variables:
     30: !     A     operator matrix
     31: !     eps   eigenproblem solver context

     33:       Mat            A
     34:       EPS            eps
     35:       EPSType        tname
     36:       PetscInt       n, i, Istart, Iend
     37:       PetscInt       nev
     38:       PetscInt       col(3)
     39:       PetscInt       i1,i2,i3
     40:       PetscMPIInt    rank
     41:       PetscErrorCode ierr
     42:       PetscBool      flg
     43:       PetscScalar    value(3)

     45: !  Note: Any user-defined Fortran routines (such as MyEPSMonitor)
     46: !  MUST be declared as external.

     48:       external MyEPSMonitor

     50: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     51: !     Beginning of program
     52: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

     54:       call SlepcInitialize(PETSC_NULL_CHARACTER,ierr)
     55:       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)
     56:       n = 30
     57:       call PetscOptionsGetInt(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,  &
     58:      &                        '-n',n,flg,ierr)

     60:       if (rank .eq. 0) then
     61:         write(*,100) n
     62:       endif
     63:  100  format (/'1-D Laplacian Eigenproblem, n =',I3,' (Fortran)')

     65: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     66: !     Compute the operator matrix that defines the eigensystem, Ax=kx
     67: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

     69:       call MatCreate(PETSC_COMM_WORLD,A,ierr)
     70:       call MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n,ierr)
     71:       call MatSetFromOptions(A,ierr)
     72:       call MatSetUp(A,ierr)

     74:       i1 = 1
     75:       i2 = 2
     76:       i3 = 3
     77:       call MatGetOwnershipRange(A,Istart,Iend,ierr)
     78:       if (Istart .eq. 0) then
     79:         i = 0
     80:         col(1) = 0
     81:         col(2) = 1
     82:         value(1) =  2.0
     83:         value(2) = -1.0
     84:         call MatSetValues(A,i1,i,i2,col,value,INSERT_VALUES,ierr)
     85:         Istart = Istart+1
     86:       endif
     87:       if (Iend .eq. n) then
     88:         i = n-1
     89:         col(1) = n-2
     90:         col(2) = n-1
     91:         value(1) = -1.0
     92:         value(2) =  2.0
     93:         call MatSetValues(A,i1,i,i2,col,value,INSERT_VALUES,ierr)
     94:         Iend = Iend-1
     95:       endif
     96:       value(1) = -1.0
     97:       value(2) =  2.0
     98:       value(3) = -1.0
     99:       do i=Istart,Iend-1
    100:         col(1) = i-1
    101:         col(2) = i
    102:         col(3) = i+1
    103:         call MatSetValues(A,i1,i,i3,col,value,INSERT_VALUES,ierr)
    104:       enddo

    106:       call MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY,ierr)
    107:       call MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY,ierr)

    109: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    110: !     Create the eigensolver and display info
    111: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    113: !     ** Create eigensolver context
    114:       call EPSCreate(PETSC_COMM_WORLD,eps,ierr)

    116: !     ** Set operators. In this case, it is a standard eigenvalue problem
    117:       call EPSSetOperators(eps,A,PETSC_NULL_MAT,ierr)
    118:       call EPSSetProblemType(eps,EPS_HEP,ierr)

    120: !     ** Set user-defined monitor
    121:       call PetscOptionsHasName(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER, &
    122:      &                        '-my_eps_monitor',flg,ierr)
    123:       if (flg) then
    124:         call EPSMonitorSet(eps,MyEPSMonitor,0,PETSC_NULL_FUNCTION,ierr)
    125:       endif

    127: !     ** Set solver parameters at runtime
    128:       call EPSSetFromOptions(eps,ierr)

    130: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    131: !     Solve the eigensystem
    132: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    134:       call EPSSolve(eps,ierr)

    136: !     ** Optional: Get some information from the solver and display it
    137:       call EPSGetType(eps,tname,ierr)
    138:       if (rank .eq. 0) then
    139:         write(*,120) tname
    140:       endif
    141:  120  format (' Solution method: ',A)
    142:       call EPSGetDimensions(eps,nev,PETSC_NULL_INTEGER,                 &
    143:      &                      PETSC_NULL_INTEGER,ierr)
    144:       if (rank .eq. 0) then
    145:         write(*,130) nev
    146:       endif
    147:  130  format (' Number of requested eigenvalues:',I2)

    149: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    150: !     Display solution and clean up
    151: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    153:       call EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_NULL_VIEWER,ierr)
    154:       call EPSDestroy(eps,ierr)
    155:       call MatDestroy(A,ierr)

    157:       call SlepcFinalize(ierr)
    158:       end

    160: ! --------------------------------------------------------------
    161: !
    162: !  MyEPSMonitor - This is a user-defined routine for monitoring
    163: !  the EPS iterative solvers.
    164: !
    165: !  Input Parameters:
    166: !    eps   - eigensolver context
    167: !    its   - iteration number
    168: !    nconv - number of converged eigenpairs
    169: !    eigr  - real part of the eigenvalues
    170: !    eigi  - imaginary part of the eigenvalues
    171: !    errest- relative error estimates for each eigenpair
    172: !    nest  - number of error estimates
    173: !    dummy - optional user-defined monitor context (unused here)
    174: !
    175:       subroutine MyEPSMonitor(eps,its,nconv,eigr,eigi,errest,nest,dummy,&
    176:      &                        ierr)
    177: #include <slepc/finclude/slepceps.h>
    178:       use slepceps
    179:       implicit none

    181:       EPS            eps
    182:       PetscErrorCode ierr
    183:       PetscInt       its,nconv,nest,dummy
    184:       PetscScalar    eigr(*),eigi(*)
    185:       PetscReal      re,errest(*)
    186:       PetscMPIInt    rank

    188:       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)
    189:       if (its .gt. 0 .and. rank .eq. 0) then
    190:         re = PetscRealPart(eigr(nconv+1))
    191:         write(6,140) its,nconv,re,errest(nconv+1)
    192:       endif

    194:  140  format(i3,' EPS nconv=',i2,' first unconverged value (error) ',   &
    195:      &       f7.4,' (',g10.3,')')
    196:       ierr = 0
    197:       end

    199: !/*TEST
    200: !
    201: !   test:
    202: !      suffix: 1
    203: !      args: -my_eps_monitor
    204: !      requires: double
    205: !
    206: !TEST*/