Actual source code: ex20f90.F90

  1: !
  2: !
  3: !
  4: ! -----------------------------------------------------------------------

  6:       program main

  8: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 10: !
 11: !
 12: !     This examples uses Fortran 90 MODULES instead of include files
 13: !
 14: #include <petsc/finclude/petscvec.h>
 15:       use petscvec
 16:       implicit none

 18: !
 19: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 20: !                   Variable declarations
 21: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 22: !
 23: !  Variables:
 24: !     x, y, w - vectors
 25: !     z       - array of vectors
 26: !
 27:       type(tVec)       x,y,w
 28:       type(tVec), pointer :: z(:)

 30:       PetscReal norm,v,v1,v2,tol
 31:       PetscInt  n,ithree
 32:       PetscErrorCode ierr
 33:       PetscMPIInt  rank
 34:       PetscBool       flg
 35:       PetscScalar      one,two,three
 36:       PetscScalar      dots(3),dot
 37:       PetscReal        nfloat

 39: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 40: !                 Beginning of program
 41: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

 43:       call PetscInitialize(PETSC_NULL_CHARACTER,ierr)
 44:       if (ierr .ne. 0) then
 45:          print*,'Unable to initialize PETSc'
 46:          stop
 47:       endif

 49:       tol   = 1.e-10_PETSC_REAL_KIND
 50:       one   = 1.0
 51:       two   = 2.0
 52:       three = 3.0
 53:       n     = 20
 54:       ithree = 3

 56:       call PetscOptionsGetInt(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-n',n,flg,ierr);CHKERRA(ierr)
 57:       nfloat = n
 58:       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr);CHKERRA(ierr)

 60: !  Create a vector, specifying only its global dimension.
 61: !  When using VecCreate(), VecSetSizes() and VecSetFromOptions(),
 62: !  the vector format (currently parallel
 63: !  or sequential) is determined at runtime.  Also, the parallel
 64: !  partitioning of the vector is determined by PETSc at runtime.
 65: !
 66: !  Routines for creating particular vector types directly are:
 67: !     VecCreateSeq() - uniprocessor vector
 68: !     VecCreateMPI() - distributed vector, where the user can
 69: !                      determine the parallel partitioning

 71:       call VecCreate(PETSC_COMM_WORLD,x,ierr);CHKERRA(ierr)
 72:       call VecSetSizes(x,PETSC_DECIDE,n,ierr);CHKERRA(ierr)
 73:       call VecSetFromOptions(x,ierr);CHKERRA(ierr)

 75: !  Duplicate some work vectors (of the same format and
 76: !  partitioning as the initial vector).

 78:       call VecDuplicate(x,y,ierr);CHKERRA(ierr)
 79:       call VecDuplicate(x,w,ierr);CHKERRA(ierr)

 81: !  Duplicate more work vectors (of the same format and
 82: !  partitioning as the initial vector).  Here we duplicate
 83: !  an array of vectors, which is often more convenient than
 84: !  duplicating individual ones.

 86:       call VecDuplicateVecsF90(x,ithree,z,ierr);CHKERRA(ierr)

 88: !  Set the vectors to entries to a constant value.

 90:       call VecSet(x,one,ierr);CHKERRA(ierr)
 91:       call VecSet(y,two,ierr);CHKERRA(ierr)
 92:       call VecSet(z(1),one,ierr);CHKERRA(ierr)
 93:       call VecSet(z(2),two,ierr);CHKERRA(ierr)
 94:       call VecSet(z(3),three,ierr);CHKERRA(ierr)

 96: !  Demonstrate various basic vector routines.

 98:       call VecDot(x,x,dot,ierr);CHKERRA(ierr)
 99:       call VecMDot(x,ithree,z,dots,ierr);CHKERRA(ierr)

101: !  Note: If using a complex numbers version of PETSc, then
102: !  PETSC_USE_COMPLEX is defined in the makefiles; otherwise,
103: !  (when using real numbers) it is undefined.

105:       if (rank .eq. 0) then
106: #if defined(PETSC_USE_COMPLEX)
107:          write(6,100) int(PetscRealPart(dot))
108:          write(6,110) int(PetscRealPart(dots(1))),int(PetscRealPart(dots(2))),int(PetscRealPart(dots(3)))
109: #else
110:          write(6,100) int(dot)
111:          write(6,110) int(dots(1)),int(dots(2)),int(dots(3))
112: #endif
113:          write(6,120)
114:       endif
115:  100  format ('Vector length ',i6)
116:  110  format ('Vector length ',3(i6))
117:  120  format ('All other values should be near zero')

119:       call VecScale(x,two,ierr);CHKERRA(ierr)
120:       call VecNorm(x,NORM_2,norm,ierr);CHKERRA(ierr)
121:       v = abs(norm-2.0*sqrt(nfloat))
122:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
123:       if (rank .eq. 0) write(6,130) v
124:  130  format ('VecScale ',1pe9.2)

126:       call VecCopy(x,w,ierr);CHKERRA(ierr)
127:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
128:       v = abs(norm-2.0*sqrt(nfloat))
129:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
130:       if (rank .eq. 0) write(6,140) v
131:  140  format ('VecCopy ',1pe9.2)

133:       call VecAXPY(y,three,x,ierr);CHKERRA(ierr)
134:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
135:       v = abs(norm-8.0*sqrt(nfloat))
136:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
137:       if (rank .eq. 0) write(6,150) v
138:  150  format ('VecAXPY ',1pe9.2)

140:       call VecAYPX(y,two,x,ierr);CHKERRA(ierr)
141:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
142:       v = abs(norm-18.0*sqrt(nfloat))
143:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
144:       if (rank .eq. 0) write(6,160) v
145:  160  format ('VecAYXP ',1pe9.2)

147:       call VecSwap(x,y,ierr);CHKERRA(ierr)
148:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
149:       v = abs(norm-2.0*sqrt(nfloat))
150:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
151:       if (rank .eq. 0) write(6,170) v
152:  170  format ('VecSwap ',1pe9.2)

154:       call VecNorm(x,NORM_2,norm,ierr);CHKERRA(ierr)
155:       v = abs(norm-18.0*sqrt(nfloat))
156:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
157:       if (rank .eq. 0) write(6,180) v
158:  180  format ('VecSwap ',1pe9.2)

160:       call VecWAXPY(w,two,x,y,ierr);CHKERRA(ierr)
161:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
162:       v = abs(norm-38.0*sqrt(nfloat))
163:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
164:       if (rank .eq. 0) write(6,190) v
165:  190  format ('VecWAXPY ',1pe9.2)

167:       call VecPointwiseMult(w,y,x,ierr);CHKERRA(ierr)
168:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
169:       v = abs(norm-36.0*sqrt(nfloat))
170:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
171:       if (rank .eq. 0) write(6,200) v
172:  200  format ('VecPointwiseMult ',1pe9.2)

174:       call VecPointwiseDivide(w,x,y,ierr);CHKERRA(ierr)
175:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
176:       v = abs(norm-9.0*sqrt(nfloat))
177:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
178:       if (rank .eq. 0) write(6,210) v
179:  210  format ('VecPointwiseDivide ',1pe9.2)

181:       dots(1) = one
182:       dots(2) = three
183:       dots(3) = two
184:       call VecSet(x,one,ierr);CHKERRA(ierr)
185:       call VecMAXPY(x,ithree,dots,z,ierr);CHKERRA(ierr)
186:       call VecNorm(z(1),NORM_2,norm,ierr);CHKERRA(ierr)
187:       v = abs(norm-sqrt(nfloat))
188:       if (v .gt. -tol .and. v .lt. tol) v = 0.0
189:       call VecNorm(z(2),NORM_2,norm,ierr);CHKERRA(ierr)
190:       v1 = abs(norm-2.0*sqrt(nfloat))
191:       if (v1 .gt. -tol .and. v1 .lt. tol) v1 = 0.0
192:       call VecNorm(z(3),NORM_2,norm,ierr);CHKERRA(ierr)
193:       v2 = abs(norm-3.0*sqrt(nfloat))
194:       if (v2 .gt. -tol .and. v2 .lt. tol) v2 = 0.0
195:       if (rank .eq. 0) write(6,220) v,v1,v2
196:  220  format ('VecMAXPY ',3(1pe9.2))

198: !  Free work space.  All PETSc objects should be destroyed when they
199: !  are no longer needed.

201:       call VecDestroy(x,ierr);CHKERRA(ierr)
202:       call VecDestroy(y,ierr);CHKERRA(ierr)
203:       call VecDestroy(w,ierr);CHKERRA(ierr)
204:       call VecDestroyVecsF90(ithree,z,ierr);CHKERRA(ierr)
205:       call PetscFinalize(ierr)

207:       end

209: !/*TEST
210: !
211: !     test:
212: !
213: !TEST*/