static char help[] = "Tests MatCopy() and MatStore/RetrieveValues().\n\n";

#include <petscmat.h>

int main(int argc, char **args)
{
  Mat         C, A;
  PetscInt    i, n = 10, midx[3], bs = 1;
  PetscScalar v[3];
  PetscBool   flg, isAIJ;
  MatType     type;
  PetscMPIInt size;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &args, NULL, help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-mat_block_size", &bs, NULL));

  PetscCall(MatCreate(PETSC_COMM_WORLD, &C));
  PetscCall(MatSetSizes(C, PETSC_DECIDE, PETSC_DECIDE, n, n));
  PetscCall(MatSetType(C, MATAIJ));
  PetscCall(MatSetFromOptions(C));
  PetscCall(PetscObjectSetName((PetscObject)C, "initial"));

  PetscCall(MatGetType(C, &type));
  if (size == 1) {
    PetscCall(PetscObjectTypeCompare((PetscObject)C, MATSEQAIJ, &isAIJ));
  } else {
    PetscCall(PetscObjectTypeCompare((PetscObject)C, MATMPIAIJ, &isAIJ));
  }
  PetscCall(MatSeqAIJSetPreallocation(C, 3, NULL));
  PetscCall(MatMPIAIJSetPreallocation(C, 3, NULL, 3, NULL));
  PetscCall(MatSeqBAIJSetPreallocation(C, bs, 3, NULL));
  PetscCall(MatMPIBAIJSetPreallocation(C, bs, 3, NULL, 3, NULL));
  PetscCall(MatSeqSBAIJSetPreallocation(C, bs, 3, NULL));
  PetscCall(MatMPISBAIJSetPreallocation(C, bs, 3, NULL, 3, NULL));

  v[0] = -1.;
  v[1] = 2.;
  v[2] = -1.;
  for (i = 1; i < n - 1; i++) {
    midx[2] = i - 1;
    midx[1] = i;
    midx[0] = i + 1;
    PetscCall(MatSetValues(C, 1, &i, 3, midx, v, INSERT_VALUES));
  }
  i       = 0;
  midx[0] = 0;
  midx[1] = 1;
  v[0]    = 2.0;
  v[1]    = -1.;
  PetscCall(MatSetValues(C, 1, &i, 2, midx, v, INSERT_VALUES));
  i       = n - 1;
  midx[0] = n - 2;
  midx[1] = n - 1;
  v[0]    = -1.0;
  v[1]    = 2.;
  PetscCall(MatSetValues(C, 1, &i, 2, midx, v, INSERT_VALUES));

  PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
  PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
  PetscCall(MatView(C, NULL));
  PetscCall(MatViewFromOptions(C, NULL, "-view"));

  /* test matduplicate */
  PetscCall(MatDuplicate(C, MAT_COPY_VALUES, &A));
  PetscCall(PetscObjectSetName((PetscObject)A, "duplicate_copy"));
  PetscCall(MatViewFromOptions(A, NULL, "-view"));
  PetscCall(MatEqual(A, C, &flg));
  PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_SUP, "MatDuplicate(C,MAT_COPY_VALUES,): Matrices are NOT equal");
  PetscCall(MatDestroy(&A));

  /* test matrices with different nonzero patterns - Note: A is created with different nonzero pattern of C! */
  PetscCall(MatCreate(PETSC_COMM_WORLD, &A));
  PetscCall(MatSetSizes(A, PETSC_DECIDE, PETSC_DECIDE, n, n));
  PetscCall(MatSetFromOptions(A));
  PetscCall(MatSetUp(A));
  PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
  PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));

  PetscCall(MatCopy(C, A, DIFFERENT_NONZERO_PATTERN));
  PetscCall(PetscObjectSetName((PetscObject)A, "copy_diffnnz"));
  PetscCall(MatViewFromOptions(A, NULL, "-view"));
  PetscCall(MatEqual(A, C, &flg));
  PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_SUP, "MatCopy(C,A,DIFFERENT_NONZERO_PATTERN): Matrices are NOT equal");

  /* test matrices with same nonzero pattern */
  PetscCall(MatDestroy(&A));
  PetscCall(MatDuplicate(C, MAT_DO_NOT_COPY_VALUES, &A));
  PetscCall(MatCopy(C, A, SAME_NONZERO_PATTERN));
  PetscCall(PetscObjectSetName((PetscObject)A, "copy_samennz"));
  PetscCall(MatViewFromOptions(A, NULL, "-view"));
  PetscCall(MatEqual(A, C, &flg));
  PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_SUP, "MatCopy(C,A,SAME_NONZERO_PATTERN): Matrices are NOT equal");

  /* test subset nonzero pattern */
  PetscCall(MatCopy(C, A, SUBSET_NONZERO_PATTERN));
  PetscCall(PetscObjectSetName((PetscObject)A, "copy_subnnz"));
  PetscCall(MatViewFromOptions(A, NULL, "-view"));
  PetscCall(MatEqual(A, C, &flg));
  PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_SUP, "MatCopy(C,A,SUBSET_NONZERO_PATTERN): Matrices are NOT equal");

  /* Test MatCopy on a matrix obtained after MatConvert from AIJ
     see https://lists.mcs.anl.gov/pipermail/petsc-dev/2019-April/024289.html */
  PetscCall(MatHasCongruentLayouts(C, &flg));
  if (flg) {
    Mat     Cs, Cse;
    MatType Ctype, Cstype;

    PetscCall(MatGetType(C, &Ctype));
    PetscCall(MatTranspose(C, MAT_INITIAL_MATRIX, &Cs));
    PetscCall(MatAXPY(Cs, 1.0, C, DIFFERENT_NONZERO_PATTERN));
    PetscCall(MatConvert(Cs, MATAIJ, MAT_INPLACE_MATRIX, &Cs));
    PetscCall(MatSetOption(Cs, MAT_SYMMETRIC, PETSC_TRUE));
    PetscCall(MatGetType(Cs, &Cstype));

    PetscCall(PetscObjectSetName((PetscObject)Cs, "symm_initial"));
    PetscCall(MatViewFromOptions(Cs, NULL, "-view"));

    PetscCall(MatConvert(Cs, Ctype, MAT_INITIAL_MATRIX, &Cse));
    PetscCall(PetscObjectSetName((PetscObject)Cse, "symm_conv_init"));
    PetscCall(MatViewFromOptions(Cse, NULL, "-view"));
    PetscCall(MatMultEqual(Cs, Cse, 5, &flg));
    PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MatConvert MAT_INITIAL_MATRIX %s -> %s: Matrices are NOT multequal", Ctype, Cstype);

    PetscCall(MatConvert(Cs, Ctype, MAT_REUSE_MATRIX, &Cse));
    PetscCall(PetscObjectSetName((PetscObject)Cse, "symm_conv_reuse"));
    PetscCall(MatViewFromOptions(Cse, NULL, "-view"));
    PetscCall(MatMultEqual(Cs, Cse, 5, &flg));
    PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MatConvert MAT_REUSE_MATRIX %s -> %s: Matrices are NOT multequal", Ctype, Cstype);

    PetscCall(MatCopy(Cs, Cse, SAME_NONZERO_PATTERN));
    PetscCall(PetscObjectSetName((PetscObject)Cse, "symm_conv_copy_samennz"));
    PetscCall(MatViewFromOptions(Cse, NULL, "-view"));
    PetscCall(MatMultEqual(Cs, Cse, 5, &flg));
    PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MatCopy(...SAME_NONZERO_PATTERN) %s -> %s: Matrices are NOT multequal", Ctype, Cstype);

    PetscCall(MatCopy(Cs, Cse, SUBSET_NONZERO_PATTERN));
    PetscCall(PetscObjectSetName((PetscObject)Cse, "symm_conv_copy_subnnz"));
    PetscCall(MatViewFromOptions(Cse, NULL, "-view"));
    PetscCall(MatMultEqual(Cs, Cse, 5, &flg));
    PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MatCopy(...SUBSET_NONZERO_PATTERN) %s -> %s: Matrices are NOT multequal", Ctype, Cstype);

    PetscCall(MatCopy(Cs, Cse, DIFFERENT_NONZERO_PATTERN));
    PetscCall(PetscObjectSetName((PetscObject)Cse, "symm_conv_copy_diffnnz"));
    PetscCall(MatViewFromOptions(Cse, NULL, "-view"));
    PetscCall(MatMultEqual(Cs, Cse, 5, &flg));
    PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "MatCopy(...DIFFERENT_NONZERO_PATTERN) %s -> %s: Matrices are NOT multequal", Ctype, Cstype);

    PetscCall(MatDestroy(&Cse));
    PetscCall(MatDestroy(&Cs));
  }

  /* test MatStore/RetrieveValues() */
  if (isAIJ) {
    PetscCall(MatSetOption(A, MAT_NEW_NONZERO_LOCATIONS, PETSC_FALSE));
    PetscCall(MatStoreValues(A));
    PetscCall(MatZeroEntries(A));
    PetscCall(MatRetrieveValues(A));
  }

  PetscCall(MatDestroy(&C));
  PetscCall(MatDestroy(&A));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   testset:
      nsize: {{1 2}separate output}
      args: -view ::ascii_info -mat_type {{aij baij sbaij mpiaij mpibaij mpisbaij}separate output} -mat_block_size {{1 2}separate output}

TEST*/