Host Matrices

Host Matrix (CRS)

template<typename NumType>
class HostMatrix : public BaseMatrix<NumType>

Implementation of a Matrix class on the host system.

Template Parameters

• NumType: Number type (double and float currently supported). This class uses the Compressed Row Storage (CRS) format.

Public Functions

HostMatrix()

Default constructor.

virtual ~HostMatrix()

Destructor.

virtual void allocate(int m, int n, int nnz)

Allocate a matrix of size m x n with nnz non-zero entries.

Parameters

• m: The number of rows.
• n: The number of columns.
• nnz: The number of non-zero entries.

virtual void clear()

Clear matrix.

virtual void copy_from(const NumType *val, const int *row_ptr, const int *col_idx)

Copy data to the matrix.

Note

allocate should be called first.

Parameters

• val: The pointer to the values to copy.
• row_ptr: The pointer to the indices of val starting a new row.
• col_idx: The pointer to the column indices of the elements in val.

virtual void copy_from(const BaseMatrix<NumType> &B)

A = B, where A is the matrix itself.

Parameters

• B: The matrix to copy.

virtual void copy_to(BaseMatrix<NumType> &B) const

B = A, where A is the matrix itself.

Parameters

• B: The matrix to copy to.

virtual NumType norm() const

Return

The Frobenius norm of the matrix.

virtual void scale(NumType alpha)

A = alpha * A, where A is the matrix itself.

Parameters

• alpha: The value by which to scale the entries in the matrix.

virtual void multiply(const BaseVector<NumType> &v_in, BaseVector<NumType> *w_out) const

w_out = A * v_in, where A is the matrix itself.

Parameters

• v_in: The vector right-multiplying the vector.
• w_out: The outputted vector.

virtual void lower_solve(const BaseVector<NumType> &b, BaseVector<NumType> *x) const

Solvers for x in (L + D) * x = b, where L and D are respectively the lower triangular and diagonal parts of the matrix itself. \param[in] b The vector in the above equation \param[out] x The vector in the above equation

virtual void upper_solve(const BaseVector<NumType> &b, BaseVector<NumType> *x) const

Solvers for x in (U + D) * x = b, where U and D are respectively the upper triangular and diagonal parts of the matrix itself. \param[in] b The vector in the above equation \param[out] x The vector in the above equation

virtual void get_diagonals(BaseVector<NumType> *diag) const

Outputs the diagonal entries of the matrix.

Parameters

• w_out: The outputted vector storing the diagonal entries.

virtual void compute_inverse_diagonals(BaseVector<NumType> *inv_diag) const

Compute the inverse of the diagonal entries of the matrix.

Parameters

• w_out: The outputted vector storing the inverse of the diagonal entries.

bool read_matrix_market(const std::string filename)

Read a matrix market.

Return

True if successfully read, and False otherwise.

Parameters

• filename: The matrix market file.

Host Matrix (COO)

template<typename NumType>
class HostMatrixCOO : public BaseMatrix<NumType>

Implementation of a Matrix class on the host system.

Template Parameters

• NumType: Number type (double and float currently supported). This class uses the Coordinate list (COO) format.

Public Functions

HostMatrixCOO()

Default constructor.

~HostMatrixCOO()

Destructor.

void allocate(int m, int n, int nnz)

Allocate a matrix of size m x n with nnz non-zero entries.

Parameters

• m: The number of rows.
• n: The number of columns.
• nnz: The number of non-zero entries.

void clear()

Clear matrix.

void copy_from(const BaseMatrix<NumType> &B)

A = B, where A is the matrix itself.

Parameters

• B: The matrix to copy.

void copy_to(BaseMatrix<NumType> &B) const

B = A, where A is the matrix itself.

Parameters

• B: The matrix to copy to.

NumType norm() const

Return

The Frobenius norm of the matrix.

void scale(NumType alpha)

A = alpha * A, where A is the matrix itself.

Parameters

• alpha: The value by which to scale the entries in the matrix.

void multiply(const BaseVector<NumType> &v_in, BaseVector<NumType> *w_out) const

w_out = A * v_in, where A is the matrix itself.

Parameters

• v_in: The vector right-multiplying the vector.
• w_out: The outputted vector.

void lower_solve(const BaseVector<NumType> &b, BaseVector<NumType> *x) const

Solvers for x in (L + D) * x = b, where L and D are respectively the lower triangular and diagonal parts of the matrix itself. \param[in] b The vector in the above equation \param[out] x The vector in the above equation

void upper_solve(const BaseVector<NumType> &b, BaseVector<NumType> *x) const

Solvers for x in (U + D) * x = b, where U and D are respectively the upper triangular and diagonal parts of the matrix itself. \param[in] b The vector in the above equation \param[out] x The vector in the above equation

void get_diagonals(BaseVector<NumType> *diag) const

Outputs the diagonal entries of the matrix.

Parameters

• w_out: The outputted vector storing the diagonal entries.

void compute_inverse_diagonals(BaseVector<NumType> *inv_diag) const

Compute the inverse of the diagonal entries of the matrix.

Parameters

• w_out: The outputted vector storing the inverse of the diagonal entries.

bool read_matrix_market(const std::string filename)

Read a matrix market.

Return

True if successfully read, and False otherwise.

Parameters

• filename: The matrix market file.

void convert_to_CSR(HostMatrix<NumType> &mat_csr) const

Convert the COO matrix to a CSR matrix.

Parameters

• mat_CSR: The CSR matrix.