Date: 2026-06-01T23:13:48+00:00

Actual source code: trajvisualization.c

      1: #include <petsc/private/tsimpl.h>

      3: static PetscErrorCode OutputBIN(MPI_Comm comm, const char *filename, PetscViewer *viewer)
      4: {
      5:   PetscFunctionBegin;
      6:   PetscCall(PetscViewerCreate(comm, viewer));
      7:   PetscCall(PetscViewerSetType(*viewer, PETSCVIEWERBINARY));
      8:   PetscCall(PetscViewerFileSetMode(*viewer, FILE_MODE_WRITE));
      9:   PetscCall(PetscViewerFileSetName(*viewer, filename));
     10:   PetscFunctionReturn(PETSC_SUCCESS);
     11: }

     13: static PetscErrorCode TSTrajectorySet_Visualization(TSTrajectory tj, TS ts, PetscInt stepnum, PetscReal time, Vec X)
     14: {
     15:   PetscViewer viewer;
     16:   char        filename[PETSC_MAX_PATH_LEN];
     17:   PetscReal   tprev;
     18:   MPI_Comm    comm;

     20:   PetscFunctionBegin;
     21:   PetscCall(PetscObjectGetComm((PetscObject)ts, &comm));
     22:   if (stepnum == 0) {
     23:     PetscMPIInt rank;
     24:     PetscCallMPI(MPI_Comm_rank(comm, &rank));
     25:     if (rank == 0) {
     26:       PetscCall(PetscRMTree("Visualization-data"));
     27:       PetscCall(PetscMkdir("Visualization-data"));
     28:     }
     29:     if (tj->names) {
     30:       PetscViewer bnames;
     31:       PetscCall(PetscViewerBinaryOpen(comm, "Visualization-data/variablenames", FILE_MODE_WRITE, &bnames));
     32:       PetscCall(PetscViewerBinaryWriteStringArray(bnames, (const char *const *)tj->names));
     33:       PetscCall(PetscViewerDestroy(&bnames));
     34:     }
     35:     PetscCall(PetscSNPrintf(filename, sizeof(filename), "Visualization-data/SA-%06" PetscInt_FMT ".bin", stepnum));
     36:     PetscCall(OutputBIN(comm, filename, &viewer));
     37:     if (!tj->transform) {
     38:       PetscCall(VecView(X, viewer));
     39:     } else {
     40:       Vec XX;
     41:       PetscCall((*tj->transform)(tj->transformctx, X, &XX));
     42:       PetscCall(VecView(XX, viewer));
     43:       PetscCall(VecDestroy(&XX));
     44:     }
     45:     PetscCall(PetscViewerBinaryWrite(viewer, &time, 1, PETSC_REAL));
     46:     PetscCall(PetscViewerDestroy(&viewer));
     47:     PetscFunctionReturn(PETSC_SUCCESS);
     48:   }
     49:   PetscCall(PetscSNPrintf(filename, sizeof(filename), "Visualization-data/SA-%06" PetscInt_FMT ".bin", stepnum));
     50:   PetscCall(OutputBIN(comm, filename, &viewer));
     51:   if (!tj->transform) {
     52:     PetscCall(VecView(X, viewer));
     53:   } else {
     54:     Vec XX;
     55:     PetscCall((*tj->transform)(tj->transformctx, X, &XX));
     56:     PetscCall(VecView(XX, viewer));
     57:     PetscCall(VecDestroy(&XX));
     58:   }
     59:   PetscCall(PetscViewerBinaryWrite(viewer, &time, 1, PETSC_REAL));

     61:   PetscCall(TSGetPrevTime(ts, &tprev));
     62:   PetscCall(PetscViewerBinaryWrite(viewer, &tprev, 1, PETSC_REAL));

     64:   PetscCall(PetscViewerDestroy(&viewer));
     65:   PetscFunctionReturn(PETSC_SUCCESS);
     66: }

     68: /*MC
     69:   TSTRAJECTORYVISUALIZATION - Stores each solution of the ODE/DAE in a file for later visualization

     71:   Saves each timestep into a separate file in `Visualization-data/SA-%06d.bin`

     73:   This version saves only the solutions at each timestep, it does not save the solution at each stage,
     74:   see `TSTRAJECTORYBASIC` that saves all stages

     76:   $PETSC_DIR/share/petsc/matlab/PetscReadBinaryTrajectory.m and $PETSC_DIR/lib/petsc/bin/PetscBinaryIOTrajectory.py
     77:   can read in files created with this format into MATLAB and Python.

     79:   Level: intermediate

     81: .seealso: [](ch_ts), `TSTrajectoryCreate()`, `TS`, `TSTrajectorySetType()`, `TSTrajectoryType`, `TSTrajectorySetVariableNames()`,
     82:           `TSTrajectory`
     83: M*/
     84: PETSC_EXTERN PetscErrorCode TSTrajectoryCreate_Visualization(TSTrajectory tj, TS ts)
     85: {
     86:   PetscFunctionBegin;
     87:   tj->ops->set    = TSTrajectorySet_Visualization;
     88:   tj->setupcalled = PETSC_TRUE;
     89:   PetscFunctionReturn(PETSC_SUCCESS);
     90: }