Actual source code: ex1f90.F90

  1:       program main
  2: #include <petsc/finclude/petscvec.h>
  3:       use petscvec
  4:       implicit none

  6: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  7: !                   Variable declarations
  8: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: !
 10: !  Variables:
 11: !     x, y, w - vectors
 12: !     z       - array of vectors
 13: !
 14:       Vec              x,y,w
 15:       Vec, pointer :: z(:)
 16:       PetscReal norm,v,v1,v2
 17:       PetscInt         n,ithree
 18:       PetscErrorCode   ierr
 19:       PetscMPIInt      rank
 20:       PetscBool        flg
 21:       PetscScalar      one,two,three
 22:       PetscScalar      dots(3),dot
 23:       PetscReal        nfloat

 25: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 26: !                 Beginning of program
 27: ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

 29:       PetscCallA(PetscInitialize(ierr))
 30:       one   = 1.0
 31:       two   = 2.0
 32:       three = 3.0
 33:       n     = 20
 34:       ithree = 3

 36:       PetscCallA(PetscOptionsGetInt(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-n',n,flg,ierr))
 37:       nfloat = n
 38:       PetscCallMPIA(MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr))

 40: !  Create a vector, specifying only its global dimension.
 41: !  When using VecCreate(), VecSetSizes() and VecSetFromOptions(),
 42: !  the vector format (currently parallel
 43: !  or sequential) is determined at runtime.  Also, the parallel
 44: !  partitioning of the vector is determined by PETSc at runtime.

 46:       PetscCallA(VecCreate(PETSC_COMM_WORLD,x,ierr))
 47:       PetscCallA(VecSetSizes(x,PETSC_DECIDE,n,ierr))
 48:       PetscCallA(VecSetFromOptions(x,ierr))

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

 53:       PetscCallA(VecDuplicate(x,y,ierr))
 54:       PetscCallA(VecDuplicate(x,w,ierr))

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

 61:       PetscCallA(VecDuplicateVecsF90(x,ithree,z,ierr))

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

 65:       PetscCallA(VecSet(x,one,ierr))
 66:       PetscCallA(VecSet(y,two,ierr))
 67:       PetscCallA(VecSet(z(1),one,ierr))
 68:       PetscCallA(VecSet(z(2),two,ierr))
 69:       PetscCallA(VecSet(z(3),three,ierr))

 71: !  Demonstrate various basic vector routines.

 73:       PetscCallA(VecDot(x,x,dot,ierr))
 74:       PetscCallA(VecMDot(x,ithree,z,dots,ierr))

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

 80:       if (rank .eq. 0) then
 81: #if defined(PETSC_USE_COMPLEX)
 82:          write(6,100) int(PetscRealPart(dot))
 83:          write(6,110) int(PetscRealPart(dots(1))),int(PetscRealPart(dots(2))),int(PetscRealPart(dots(3)))
 84: #else
 85:          write(6,100) int(dot)
 86:          write(6,110) int(dots(1)),int(dots(2)),int(dots(3))
 87: #endif
 88:          write(6,120)
 89:       endif
 90:  100  format ('Vector length ',i6)
 91:  110  format ('Vector length ',3(i6))
 92:  120  format ('All other values should be near zero')

 94:       PetscCallA(VecScale(x,two,ierr))
 95:       PetscCallA(VecNorm(x,NORM_2,norm,ierr))
 96:       v = abs(norm-2.0*sqrt(nfloat))
 97:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
 98:       if (rank .eq. 0) write(6,130) v
 99:  130  format ('VecScale ',1pe9.2)

101:       PetscCallA(VecCopy(x,w,ierr))
102:       PetscCallA(VecNorm(w,NORM_2,norm,ierr))
103:       v = abs(norm-2.0*sqrt(nfloat))
104:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
105:       if (rank .eq. 0) write(6,140) v
106:  140  format ('VecCopy ',1pe9.2)

108:       PetscCallA(VecAXPY(y,three,x,ierr))
109:       PetscCallA(VecNorm(y,NORM_2,norm,ierr))
110:       v = abs(norm-8.0*sqrt(nfloat))
111:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
112:       if (rank .eq. 0) write(6,150) v
113:  150  format ('VecAXPY ',1pe9.2)

115:       PetscCallA(VecAYPX(y,two,x,ierr))
116:       PetscCallA(VecNorm(y,NORM_2,norm,ierr))
117:       v = abs(norm-18.0*sqrt(nfloat))
118:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
119:       if (rank .eq. 0) write(6,160) v
120:  160  format ('VecAYXP ',1pe9.2)

122:       PetscCallA(VecSwap(x,y,ierr))
123:       PetscCallA(VecNorm(y,NORM_2,norm,ierr))
124:       v = abs(norm-2.0*sqrt(nfloat))
125:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
126:       if (rank .eq. 0) write(6,170) v
127:  170  format ('VecSwap ',1pe9.2)

129:       PetscCallA(VecNorm(x,NORM_2,norm,ierr))
130:       v = abs(norm-18.0*sqrt(nfloat))
131:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
132:       if (rank .eq. 0) write(6,180) v
133:  180  format ('VecSwap ',1pe9.2)

135:       PetscCallA(VecWAXPY(w,two,x,y,ierr))
136:       PetscCallA(VecNorm(w,NORM_2,norm,ierr))
137:       v = abs(norm-38.0*sqrt(nfloat))
138:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
139:       if (rank .eq. 0) write(6,190) v
140:  190  format ('VecWAXPY ',1pe9.2)

142:       PetscCallA(VecPointwiseMult(w,y,x,ierr))
143:       PetscCallA(VecNorm(w,NORM_2,norm,ierr))
144:       v = abs(norm-36.0*sqrt(nfloat))
145:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
146:       if (rank .eq. 0) write(6,200) v
147:  200  format ('VecPointwiseMult ',1pe9.2)

149:       PetscCallA(VecPointwiseDivide(w,x,y,ierr))
150:       PetscCallA(VecNorm(w,NORM_2,norm,ierr))
151:       v = abs(norm-9.0*sqrt(nfloat))
152:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
153:       if (rank .eq. 0) write(6,210) v
154:  210  format ('VecPointwiseDivide ',1pe9.2)

156:       dots(1) = one
157:       dots(2) = three
158:       dots(3) = two
159:       PetscCallA(VecSet(x,one,ierr))
160:       PetscCallA(VecMAXPY(x,ithree,dots,z,ierr))
161:       PetscCallA(VecNorm(z(1),NORM_2,norm,ierr))
162:       v = abs(norm-sqrt(nfloat))
163:       if (v .gt. -1.d-10 .and. v .lt. 1.d-10) v = 0.0
164:       PetscCallA(VecNorm(z(2),NORM_2,norm,ierr))
165:       v1 = abs(norm-2.0*sqrt(nfloat))
166:       if (v1 .gt. -1.d-10 .and. v1 .lt. 1.d-10) v1 = 0.0
167:       PetscCallA(VecNorm(z(3),NORM_2,norm,ierr))
168:       v2 = abs(norm-3.0*sqrt(nfloat))
169:       if (v2 .gt. -1.d-10 .and. v2 .lt. 1.d-10) v2 = 0.0
170:       if (rank .eq. 0) write(6,220) v,v1,v2
171:  220  format ('VecMAXPY ',3(1pe9.2))

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

176:       PetscCallA(VecDestroy(x,ierr))
177:       PetscCallA(VecDestroy(y,ierr))
178:       PetscCallA(VecDestroy(w,ierr))
179:       PetscCallA(VecDestroyVecsF90(ithree,z,ierr))
180:       PetscCallA(PetscFinalize(ierr))

182:       end

184: !
185: !/*TEST
186: !
187: !     test:
188: !       nsize: 2
189: !
190: !TEST*/