Actual source code: ex1f90.F90

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

  6:       program main
  7: #include <petsc/finclude/petscvec.h>
  8:       use petscvec
  9:       implicit none

 11: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 12: !                   Variable declarations
 13: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 14: !
 15: !  Variables:
 16: !     x, y, w - vectors
 17: !     z       - array of vectors
 18: !
 19:       Vec              x,y,w
 20:       Vec, pointer :: z(:)
 21:       PetscReal norm,v,v1,v2
 22:       PetscInt         n,ithree
 23:       PetscErrorCode   ierr
 24:       PetscMPIInt      rank
 25:       PetscBool        flg
 26:       PetscScalar      one,two,three
 27:       PetscScalar      dots(3),dot
 28:       PetscReal        nfloat

 30: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 31: !                 Beginning of program
 32: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

 34:       call PetscInitialize(PETSC_NULL_CHARACTER,ierr)
 35:       if (ierr .ne. 0) then
 36:         print*,'Unable to initialize PETSc'
 37:         stop
 38:       endif
 39:       one   = 1.0
 40:       two   = 2.0
 41:       three = 3.0
 42:       n     = 20
 43:       ithree = 3

 45:       call PetscOptionsGetInt(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-n',n,flg,ierr);CHKERRA(ierr)
 46:       nfloat = n
 47:       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr);CHKERRA(ierr)

 49: !  Create a vector, specifying only its global dimension.
 50: !  When using VecCreate(), VecSetSizes() and VecSetFromOptions(),
 51: !  the vector format (currently parallel
 52: !  or sequential) is determined at runtime.  Also, the parallel
 53: !  partitioning of the vector is determined by PETSc at runtime.
 54: !
 55: !  Routines for creating particular vector types directly are:
 56: !     VecCreateSeq() - uniprocessor vector
 57: !     VecCreateMPI() - distributed vector, where the user can
 58: !                      determine the parallel partitioning

 60:       call VecCreate(PETSC_COMM_WORLD,x,ierr);CHKERRA(ierr)
 61:       call VecSetSizes(x,PETSC_DECIDE,n,ierr);CHKERRA(ierr)
 62:       call VecSetFromOptions(x,ierr);CHKERRA(ierr)

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

 67:       call VecDuplicate(x,y,ierr);CHKERRA(ierr)
 68:       call VecDuplicate(x,w,ierr);CHKERRA(ierr)

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

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

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

 79:       call VecSet(x,one,ierr);CHKERRA(ierr)
 80:       call VecSet(y,two,ierr);CHKERRA(ierr)
 81:       call VecSet(z(1),one,ierr);CHKERRA(ierr)
 82:       call VecSet(z(2),two,ierr);CHKERRA(ierr)
 83:       call VecSet(z(3),three,ierr);CHKERRA(ierr)

 85: !  Demonstrate various basic vector routines.

 87:       call VecDot(x,x,dot,ierr);CHKERRA(ierr)
 88:       call VecMDot(x,ithree,z,dots,ierr);CHKERRA(ierr)

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

 94:       if (rank .eq. 0) then
 95: #if defined(PETSC_USE_COMPLEX)
 96:          write(6,100) int(PetscRealPart(dot))
 97:          write(6,110) int(PetscRealPart(dots(1))),int(PetscRealPart(dots(2))),int(PetscRealPart(dots(3)))
 98: #else
 99:          write(6,100) int(dot)
100:          write(6,110) int(dots(1)),int(dots(2)),int(dots(3))
101: #endif
102:          write(6,120)
103:       endif
104:  100  format ('Vector length ',i6)
105:  110  format ('Vector length ',3(i6))
106:  120  format ('All other values should be near zero')

108:       call VecScale(x,two,ierr);CHKERRA(ierr)
109:       call VecNorm(x,NORM_2,norm,ierr);CHKERRA(ierr)
110:       v = abs(norm-2.0*sqrt(nfloat))
111:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
112:       if (rank .eq. 0) write(6,130) v
113:  130  format ('VecScale ',1pe9.2)

115:       call VecCopy(x,w,ierr);CHKERRA(ierr)
116:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
117:       v = abs(norm-2.0*sqrt(nfloat))
118:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
119:       if (rank .eq. 0) write(6,140) v
120:  140  format ('VecCopy ',1pe9.2)

122:       call VecAXPY(y,three,x,ierr);CHKERRA(ierr)
123:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
124:       v = abs(norm-8.0*sqrt(nfloat))
125:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
126:       if (rank .eq. 0) write(6,150) v
127:  150  format ('VecAXPY ',1pe9.2)

129:       call VecAYPX(y,two,x,ierr);CHKERRA(ierr)
130:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
131:       v = abs(norm-18.0*sqrt(nfloat))
132:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
133:       if (rank .eq. 0) write(6,160) v
134:  160  format ('VecAYXP ',1pe9.2)

136:       call VecSwap(x,y,ierr);CHKERRA(ierr)
137:       call VecNorm(y,NORM_2,norm,ierr);CHKERRA(ierr)
138:       v = abs(norm-2.0*sqrt(nfloat))
139:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
140:       if (rank .eq. 0) write(6,170) v
141:  170  format ('VecSwap ',1pe9.2)

143:       call VecNorm(x,NORM_2,norm,ierr);CHKERRA(ierr)
144:       v = abs(norm-18.0*sqrt(nfloat))
145:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
146:       if (rank .eq. 0) write(6,180) v
147:  180  format ('VecSwap ',1pe9.2)

149:       call VecWAXPY(w,two,x,y,ierr);CHKERRA(ierr)
150:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
151:       v = abs(norm-38.0*sqrt(nfloat))
152:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
153:       if (rank .eq. 0) write(6,190) v
154:  190  format ('VecWAXPY ',1pe9.2)

156:       call VecPointwiseMult(w,y,x,ierr);CHKERRA(ierr)
157:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
158:       v = abs(norm-36.0*sqrt(nfloat))
159:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
160:       if (rank .eq. 0) write(6,200) v
161:  200  format ('VecPointwiseMult ',1pe9.2)

163:       call VecPointwiseDivide(w,x,y,ierr);CHKERRA(ierr)
164:       call VecNorm(w,NORM_2,norm,ierr);CHKERRA(ierr)
165:       v = abs(norm-9.0*sqrt(nfloat))
166:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
167:       if (rank .eq. 0) write(6,210) v
168:  210  format ('VecPointwiseDivide ',1pe9.2)

170:       dots(1) = one
171:       dots(2) = three
172:       dots(3) = two
173:       call VecSet(x,one,ierr);CHKERRA(ierr)
174:       call VecMAXPY(x,ithree,dots,z,ierr);CHKERRA(ierr)
175:       call VecNorm(z(1),NORM_2,norm,ierr);CHKERRA(ierr)
176:       v = abs(norm-sqrt(nfloat))
177:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
178:       call VecNorm(z(2),NORM_2,norm,ierr);CHKERRA(ierr)
179:       v1 = abs(norm-2.0*sqrt(nfloat))
180:       if (v1 .gt. -1.d-10 .and. v1 .lt. 1.d-10) v1 = 0.0
181:       call VecNorm(z(3),NORM_2,norm,ierr);CHKERRA(ierr)
182:       v2 = abs(norm-3.0*sqrt(nfloat))
183:       if (v2 .gt. -1.d-10 .and. v2 .lt. 1.d-10) v2 = 0.0
184:       if (rank .eq. 0) write(6,220) v,v1,v2
185:  220  format ('VecMAXPY ',3(1pe9.2))

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

190:       call VecDestroy(x,ierr);CHKERRA(ierr)
191:       call VecDestroy(y,ierr);CHKERRA(ierr)
192:       call VecDestroy(w,ierr);CHKERRA(ierr)
193:       call VecDestroyVecsF90(ithree,z,ierr);CHKERRA(ierr)
194:       call PetscFinalize(ierr)

196:       end

198: !
199: !/*TEST
200: !
201: !     test:
202: !       nsize: 2
203: !
204: !TEST*/