Matrix

class Matrix : public godzilla::PetscObjectWrapper<Mat>

Subclassed by godzilla::ShellMatrix

Public Functions

void set_type(const char *type)

Builds matrix object for a particular matrix type.

Parameters:

type – The matrix type

void set_values_local(Int n, const Int *row_idxs, Int m, const Int *col_idxs, const Scalar *vals, InsertMode mode = INSERT_VALUES)

Inserts or adds values into certain locations of a matrix, using a local numbering of the rows and columns.

Parameters:

  • n – Number of rows

  • row_idxs – The row local indices

  • m – Number of columns

  • col_idxs – The column local indices

  • vals – The values to insert (row-major format)

  • mode – The insertion mode

void set_values_local(const std::vector<Int> &row_idxs, const std::vector<Int> &col_idxs, const std::vector<Scalar> &vals, InsertMode mode = INSERT_VALUES)

Inserts or adds values into certain locations of a matrix, using a local numbering of the rows and columns.

Parameters:

  • row_idxs – The row local indices

  • col_idxs – The column local indices

  • vals – The values to insert

  • mode – The insertion mode

template<Int N>
inline void set_values_local(const DenseVector<Int, N> &row_idxs, const DenseVector<Int, N> &col_idxs, const DenseMatrix<Scalar, N, N> &vals, InsertMode mode = INSERT_VALUES)

Inserts or adds values into certain locations of a matrix, using a local numbering of the rows and columns.

Parameters:

  • row_idxs – The row local indices

  • col_idxs – The column local indices

  • vals – The values to insert

  • mode – The insertion mode

void set_values_local(const DynDenseVector<Int> &row_idxs, const DynDenseVector<Int> &col_idxs, const DynDenseMatrix<Scalar> &vals, InsertMode mode = INSERT_VALUES)

Inserts or adds values into certain locations of a matrix, using a local numbering of the rows and columns.

Parameters:

  • row_idxs – The row local indices

  • col_idxs – The column local indices

  • vals – The values to insert

  • mode – The insertion mode

void mult(const Vector &x, Vector &y)

Computes the matrix-vector product, y = Ax.

void scale(Scalar a)

Scales all elements of a matrix by a given number.

Parameters:

a – The scaling value

void transpose()

Computes an in-place transpose of a matrix.

void set_option(Option option, bool flag)

Sets a parameter option for a matrix.

Parameters:

  • option – The option to set

  • flag – The value of the option

void set_block_size(Int bs)

Sets the matrix block size.

Parameters:

bs – The block size

bool is_symmetric(Real tol) const

Test whether a matrix is symmetric.

Parameters:

tol – difference between value and its transpose less than this amount counts as equal (use 0.0 for exact transpose)

Returns:

true if the matrix is symmetric, false otherwise