xref: /petsc/src/snes/tests/ex18f90.F90 (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1*c4762a1bSJed Brown!
2*c4762a1bSJed Brown! Example usage of Fortran 2003/2008 classes (extended derived types) as
3*c4762a1bSJed Brown! user-defined contexts in PETSc. Example contributed by Glenn Hammond.
4*c4762a1bSJed Brown!
5*c4762a1bSJed Brownmodule Base_module
6*c4762a1bSJed Brown#include "petsc/finclude/petscsnes.h"
7*c4762a1bSJed Brown      implicit none
8*c4762a1bSJed Brown  private
9*c4762a1bSJed Brown
10*c4762a1bSJed Brown  type, public :: base_type
11*c4762a1bSJed Brown    PetscInt :: A  ! junk
12*c4762a1bSJed Brown    PetscReal :: I ! junk
13*c4762a1bSJed Brown  contains
14*c4762a1bSJed Brown    procedure, public :: Print => BasePrint
15*c4762a1bSJed Brown  end type base_type
16*c4762a1bSJed Browncontains
17*c4762a1bSJed Brownsubroutine BasePrint(this)
18*c4762a1bSJed Brown  implicit none
19*c4762a1bSJed Brown  class(base_type) :: this
20*c4762a1bSJed Brown  print *
21*c4762a1bSJed Brown  print *, 'Base printout'
22*c4762a1bSJed Brown  print *
23*c4762a1bSJed Brownend subroutine BasePrint
24*c4762a1bSJed Brownend module Base_module
25*c4762a1bSJed Brown
26*c4762a1bSJed Brownmodule Extended_module
27*c4762a1bSJed Brown  use Base_module
28*c4762a1bSJed Brown  implicit none
29*c4762a1bSJed Brown  private
30*c4762a1bSJed Brown  type, public, extends(base_type) :: extended_type
31*c4762a1bSJed Brown    PetscInt :: B  ! junk
32*c4762a1bSJed Brown    PetscReal :: J ! junk
33*c4762a1bSJed Brown  contains
34*c4762a1bSJed Brown    procedure, public :: Print =>  ExtendedPrint
35*c4762a1bSJed Brown  end type extended_type
36*c4762a1bSJed Browncontains
37*c4762a1bSJed Brownsubroutine ExtendedPrint(this)
38*c4762a1bSJed Brown  implicit none
39*c4762a1bSJed Brown  class(extended_type) :: this
40*c4762a1bSJed Brown  print *
41*c4762a1bSJed Brown  print *, 'Extended printout'
42*c4762a1bSJed Brown  print *
43*c4762a1bSJed Brownend subroutine ExtendedPrint
44*c4762a1bSJed Brownend module Extended_module
45*c4762a1bSJed Brown
46*c4762a1bSJed Brownmodule Function_module
47*c4762a1bSJed Brown  use petscsnes
48*c4762a1bSJed Brown  implicit none
49*c4762a1bSJed Brown  public :: TestFunction
50*c4762a1bSJed Brown  contains
51*c4762a1bSJed Brownsubroutine TestFunction(snes,xx,r,ctx,ierr)
52*c4762a1bSJed Brown  use Base_module
53*c4762a1bSJed Brown  implicit none
54*c4762a1bSJed Brown  SNES :: snes
55*c4762a1bSJed Brown  Vec :: xx
56*c4762a1bSJed Brown  Vec :: r
57*c4762a1bSJed Brown  class(base_type) :: ctx ! yes, this should be base_type in order to handle all
58*c4762a1bSJed Brown  PetscErrorCode :: ierr  ! polymorphic extensions
59*c4762a1bSJed Brown  call ctx%Print()
60*c4762a1bSJed Brownend subroutine TestFunction
61*c4762a1bSJed Brownend module Function_module
62*c4762a1bSJed Brown
63*c4762a1bSJed Brownprogram ex18f90
64*c4762a1bSJed Brown
65*c4762a1bSJed Brown  use Base_module
66*c4762a1bSJed Brown  use Extended_module
67*c4762a1bSJed Brown  use Function_module
68*c4762a1bSJed Brown  implicit none
69*c4762a1bSJed Brown
70*c4762a1bSJed Brown! ifort on windows requires this interface definition
71*c4762a1bSJed Browninterface
72*c4762a1bSJed Brown  subroutine SNESSetFunction(snes_base,x,TestFunction,base,ierr)
73*c4762a1bSJed Brown    use Base_module
74*c4762a1bSJed Brown    use petscsnes
75*c4762a1bSJed Brown    SNES snes_base
76*c4762a1bSJed Brown    Vec x
77*c4762a1bSJed Brown    external TestFunction
78*c4762a1bSJed Brown    class(base_type) :: base
79*c4762a1bSJed Brown    PetscErrorCode ierr
80*c4762a1bSJed Brown  end subroutine
81*c4762a1bSJed Brownend interface
82*c4762a1bSJed Brown
83*c4762a1bSJed Brown  PetscMPIInt :: size
84*c4762a1bSJed Brown  PetscMPIInt :: rank
85*c4762a1bSJed Brown
86*c4762a1bSJed Brown  SNES :: snes_base, snes_extended
87*c4762a1bSJed Brown  Vec :: x
88*c4762a1bSJed Brown  class(base_type), pointer :: base
89*c4762a1bSJed Brown  class(extended_type), pointer :: extended
90*c4762a1bSJed Brown  PetscErrorCode :: ierr
91*c4762a1bSJed Brown
92*c4762a1bSJed Brown  print *, 'Start of Fortran2003 test program'
93*c4762a1bSJed Brown
94*c4762a1bSJed Brown  nullify(base)
95*c4762a1bSJed Brown  nullify(extended)
96*c4762a1bSJed Brown  allocate(base)
97*c4762a1bSJed Brown  allocate(extended)
98*c4762a1bSJed Brown  call PetscInitialize(PETSC_NULL_CHARACTER, ierr)
99*c4762a1bSJed Brown  if (ierr .ne. 0) then
100*c4762a1bSJed Brown    print*,'Unable to initialize PETSc'
101*c4762a1bSJed Brown    stop
102*c4762a1bSJed Brown  endif
103*c4762a1bSJed Brown  call MPI_Comm_size(PETSC_COMM_WORLD,size,ierr);CHKERRA(ierr)
104*c4762a1bSJed Brown  call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr);CHKERRA(ierr)
105*c4762a1bSJed Brown
106*c4762a1bSJed Brown  call VecCreate(PETSC_COMM_WORLD,x,ierr);CHKERRA(ierr)
107*c4762a1bSJed Brown
108*c4762a1bSJed Brown  ! use the base class as the context
109*c4762a1bSJed Brown  print *
110*c4762a1bSJed Brown  print *, 'the base class will succeed by printing out Base printout below'
111*c4762a1bSJed Brown  call SNESCreate(PETSC_COMM_WORLD,snes_base,ierr);CHKERRA(ierr)
112*c4762a1bSJed Brown  call SNESSetFunction(snes_base,x,TestFunction,base,ierr);CHKERRA(ierr)
113*c4762a1bSJed Brown  call SNESComputeFunction(snes_base,x,x,ierr);CHKERRA(ierr)
114*c4762a1bSJed Brown  call SNESDestroy(snes_base,ierr);CHKERRA(ierr)
115*c4762a1bSJed Brown
116*c4762a1bSJed Brown  ! use the extended class as the context
117*c4762a1bSJed Brown  print *, 'the extended class will succeed by printing out Extended printout below'
118*c4762a1bSJed Brown  call SNESCreate(PETSC_COMM_WORLD,snes_extended,ierr);CHKERRA(ierr)
119*c4762a1bSJed Brown  call SNESSetFunction(snes_extended,x,TestFunction,extended,ierr);CHKERRA(ierr)
120*c4762a1bSJed Brown  call SNESComputeFunction(snes_extended,x,x,ierr);CHKERRA(ierr)
121*c4762a1bSJed Brown  call VecDestroy(x,ierr);CHKERRA(ierr)
122*c4762a1bSJed Brown  call SNESDestroy(snes_extended,ierr);CHKERRA(ierr)
123*c4762a1bSJed Brown  if (associated(base)) deallocate(base)
124*c4762a1bSJed Brown  if (associated(extended)) deallocate(extended)
125*c4762a1bSJed Brown  call PetscFinalize(ierr)
126*c4762a1bSJed Brown
127*c4762a1bSJed Brown  print *, 'End of Fortran2003 test program'
128*c4762a1bSJed Brown
129*c4762a1bSJed Brownend program ex18f90
130*c4762a1bSJed Brown
131*c4762a1bSJed Brown!/*TEST
132*c4762a1bSJed Brown!
133*c4762a1bSJed Brown!   build:
134*c4762a1bSJed Brown!      requires: define(PETSC_USING_F2003) define(PETSC_USING_F90FREEFORM)
135*c4762a1bSJed Brown!   test:
136*c4762a1bSJed Brown!     requires: !pgf90_compiler
137*c4762a1bSJed Brown!
138*c4762a1bSJed Brown!TEST*/
139