Actual source code: ex20f.F

  1: !
  2:       program main
  3:       implicit none
 4:  #include finclude/petscsys.h
 5:  #include finclude/petscvec.h
 6:  #include finclude/petscviewer.h

  8: !
  9: !      This example demonstrates writing an array to a file in binary
 10: !      format that may be read in by PETSc's VecLoad() routine.
 11: !
 12:        PetscInt n,i,ione
 13:        PetscErrorCode ierr
 14:        integer fd
 15:        PetscInt veccookie(1)
 16:        PetscScalar      array(5)
 17:        Vec              x
 18:        PetscViewer           v

 20:        ione         = 1
 21:        n            = 5
 22:        veccookie(1) = 1211211 + 3

 24:        call PetscInitialize(PETSC_NULL_CHARACTER,ierr)

 26:        do 10, i=1,5
 27:          array(i) = i
 28:  10    continue

 30: !      Open binary file for writing
 31:        call PetscBinaryOpen('testfile',FILE_MODE_WRITE,fd,ierr)
 32: !      Write the Vec header
 33:        call PetscBinaryWrite(fd,veccookie,ione,PETSC_INT,                    &
 34:      &                       PETSC_FALSE,ierr)
 35: !      Write the array length
 36:        call PetscBinaryWrite(fd,n,ione,PETSC_INT,PETSC_FALSE,ierr)
 37: !      Write the array
 38:        call PetscBinaryWrite(fd,array,n,PETSC_DOUBLE,PETSC_FALSE,ierr)
 39: !      Close the file
 40:        call PetscBinaryClose(fd,ierr)

 42: !
 43: !      Open the file for reading by PETSc
 44: !
 45:        call PetscViewerBinaryOpen(PETSC_COMM_SELF,'testfile',                &
 46:      &                       FILE_MODE_READ,v,ierr)
 47: !
 48: !      Load the vector
 49: !
 50:        Call VecLoad(v,PETSC_NULL_CHARACTER,x,ierr)
 51:        call PetscViewerDestroy(v,ierr)
 52: !
 53: !      Print the vector
 54: !
 55:        call VecView(x,PETSC_VIEWER_STDOUT_SELF,ierr)
 56: !

 58:        call VecDestroy(x,ierr)
 59:        call PetscFinalize(ierr)
 60:        end

 62: