static char help[] = "Tests various routines in MatMPIBAIJ format.\n";

#include <petscmat.h>

int main(int argc, char **args)
{
  Mat         A;
  PetscInt    m = 2, bs = 1, M, row, col, start, end, i, j, k;
  PetscMPIInt rank, size;
  PetscScalar data = 100;
  PetscBool   flg;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &args, NULL, help));
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));

  /* Test MatSetValues() and MatGetValues() */
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-mat_block_size", &bs, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-mat_size", &m, NULL));

  M = m * bs * size;
  PetscCall(MatCreateBAIJ(PETSC_COMM_WORLD, bs, PETSC_DECIDE, PETSC_DECIDE, M, M, PETSC_DECIDE, NULL, PETSC_DECIDE, NULL, &A));

  PetscCall(MatGetOwnershipRange(A, &start, &end));
  PetscCall(PetscOptionsHasName(NULL, NULL, "-column_oriented", &flg));
  if (flg) PetscCall(MatSetOption(A, MAT_ROW_ORIENTED, PETSC_FALSE));

  /* inproc assembly */
  for (row = start; row < end; row++) {
    for (col = start; col < end; col++, data += 1) PetscCall(MatSetValues(A, 1, &row, 1, &col, &data, INSERT_VALUES));
  }
  PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
  PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

  /* offproc assembly */
  data = 5.0;
  row  = (M + start - 1) % M;
  for (col = 0; col < M; col++) PetscCall(MatSetValues(A, 1, &row, 1, &col, &data, ADD_VALUES));
  PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
  PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

  /* Test MatSetValuesBlocked() */
  PetscCall(PetscOptionsHasName(NULL, NULL, "-test_setvaluesblocked", &flg));
  if (flg) {
    PetscScalar *bval;
    row /= bs;
    col = start / bs;
    PetscCall(PetscMalloc1(bs * bs, &bval));
    k = 1;
    /* row-oriented - default */
    for (i = 0; i < bs; i++) {
      for (j = 0; j < bs; j++) {
        bval[i * bs + j] = (PetscScalar)k;
        k++;
      }
    }
    PetscCall(MatSetValuesBlocked(A, 1, &row, 1, &col, bval, INSERT_VALUES));
    PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
    PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
    PetscCall(PetscFree(bval));
  }

  PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
  PetscCall(MatDestroy(&A));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
      suffix: 1
      nsize: 3
      args: -mat_block_size 2 -test_setvaluesblocked

   test:
      suffix: 2
      nsize: 3
      args: -mat_block_size 2 -test_setvaluesblocked -column_oriented

   test:
      suffix: 3
      nsize: 3
      args: -mat_block_size 1 -test_setvaluesblocked

   test:
      suffix: 4
      nsize: 3
      args: -mat_block_size 1 -test_setvaluesblocked -column_oriented

TEST*/