26   subroutine FormFunction(snes, x, f, dummy, ierr)  argument
29     PetscErrorCode ierr
40     PetscCall(VecGetArrayRead(x, lx_v, ierr))
41     PetscCall(VecGetArray(f, lf_v, ierr))
50     PetscCall(VecRestoreArrayRead(x, lx_v, ierr))
51     PetscCall(VecRestoreArray(f, lf_v, ierr))
68   subroutine FormJacobian(snes, X, jac, B, dummy, ierr)  argument
74     PetscErrorCode ierr
85     PetscCall(VecGetArrayRead(x, lx_v, ierr))
99     PetscCall(MatSetValues(B, i2, idx, i2, idx, A, INSERT_VALUES, ierr))
103     PetscCall(VecRestoreArrayRead(x, lx_v, ierr))
107     PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY, ierr))
108     PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY, ierr))
110       PetscCall(MatAssemblyBegin(jac, MAT_FINAL_ASSEMBLY, ierr))
111       PetscCall(MatAssemblyEnd(jac, MAT_FINAL_ASSEMBLY, ierr))
116   subroutine MyLineSearch(linesearch, lctx, ierr)  argument
123     PetscErrorCode ierr
128     PetscCall(SNESLineSearchGetSNES(linesearch, snes, ierr))
129     PetscCall(SNESLineSearchGetVecs(linesearch, x, f, y, w, g, ierr))
130     PetscCall(VecNorm(y, NORM_2, ynorm, ierr))
131     PetscCall(VecAXPY(x, mone, y, ierr))
132     PetscCall(SNESComputeFunction(snes, x, f, ierr))
133     PetscCall(VecNorm(f, NORM_2, gnorm, ierr))
134     PetscCall(VecNorm(x, NORM_2, xnorm, ierr))
135     PetscCall(VecNorm(y, NORM_2, ynorm, ierr))
136     PetscCall(SNESLineSearchSetNorms(linesearch, xnorm, gnorm, ynorm, ierr))
164   PetscErrorCode ierr
182   PetscCallA(PetscInitialize(ierr))
183   PetscCallA(PetscLogNestedBegin(ierr))
185   PetscCallA(PetscLogSetThreshold(threshold, oldthreshold, ierr))
186   PetscCallMPIA(MPI_Comm_size(PETSC_COMM_WORLD, size, ierr))
187   PetscCallMPIA(MPI_Comm_rank(PETSC_COMM_WORLD, rank, ierr))
196   PetscCallA(SNESCreate(PETSC_COMM_WORLD, snes, ierr))
198 …nceHistory(snes, PETSC_NULL_REAL_ARRAY, PETSC_NULL_INTEGER_ARRAY, PETSC_DECIDE, PETSC_FALSE, ierr))
206   PetscCallA(VecCreateSeq(PETSC_COMM_SELF, i2, x, ierr))
207   PetscCallA(VecDuplicate(x, r, ierr))
211   PetscCallA(MatCreate(PETSC_COMM_SELF, J, ierr))
212   PetscCallA(MatSetSizes(J, PETSC_DECIDE, PETSC_DECIDE, i2, i2, ierr))
213   PetscCallA(MatSetFromOptions(J, ierr))
214   PetscCallA(MatSetUp(J, ierr))
218   PetscCallA(SNESSetFunction(snes, r, FormFunction, 0, ierr))
222   PetscCallA(SNESSetJacobian(snes, J, J, FormJacobian, 0, ierr))
232   PetscCallA(SNESGetKSP(snes, ksp, ierr))
233   PetscCallA(KSPGetPC(ksp, pc, ierr))
234   PetscCallA(PCSetType(pc, PCNONE, ierr))
236   PetscCallA(KSPSetTolerances(ksp, tol, PETSC_CURRENT_REAL, PETSC_CURRENT_REAL, i20, ierr))
244   PetscCallA(SNESSetFromOptions(snes, ierr))
246   PetscCallA(PetscOptionsHasName(PETSC_NULL_OPTIONS, PETSC_NULL_CHARACTER, '-setls', setls, ierr))
249     PetscCallA(SNESGetLineSearch(snes, linesearch, ierr))
250     PetscCallA(SNESLineSearchSetType(linesearch, 'shell', ierr))
251     PetscCallA(SNESLineSearchShellSetApply(linesearch, MyLineSearch, 0, ierr))
264   PetscCallA(VecSet(x, pfive, ierr))
265   PetscCallA(SNESSolve(snes, PETSC_NULL_VEC, x, ierr))
267   PetscCallA(SNESGetConvergenceHistory(snes, rhistory, itshistory, nhistory, ierr))
268   PetscCallA(SNESRestoreConvergenceHistory(snes, rhistory, itshistory, nhistory, ierr))
271   PetscCallA(SNESConvergedReasonView(snes, PETSC_VIEWER_STDOUT_WORLD, ierr))
273   PetscCallA(SNESGetIterationNumber(snes, its, ierr))
284   PetscCallA(VecDestroy(x, ierr))
285   PetscCallA(VecDestroy(r, ierr))
286   PetscCallA(MatDestroy(J, ierr))
287   PetscCallA(SNESDestroy(snes, ierr))
289   PetscCallA(PetscViewerASCIIOpen(PETSC_COMM_WORLD, 'filename.xml', viewer, ierr))
290   PetscCallA(PetscViewerPushFormat(viewer, PETSC_VIEWER_ASCII_XML, ierr))
291   PetscCallA(PetscLogView(viewer, ierr))
292   PetscCallA(PetscViewerDestroy(viewer, ierr))
294   PetscCallA(PetscFinalize(ierr))