rocsparse_scsr2csc Interface Reference

rocsparse_scsr2csc Interface Reference#

HIPFORT API Reference: hipfort_rocsparse::rocsparse_scsr2csc Interface Reference

Convert a sparse CSR matrix into a sparse CSC matrix. More...

Public Member Functions
integer(kind(rocsparse_status_success)) function	rocsparse_scsr2csc_ (handle, m, n, nnz, csr_val, csr_row_ptr, csr_col_ind, csc_val, csc_row_ind, csc_col_ptr, copy_values, idx_base, temp_buffer)

integer(kind(rocsparse_status_success)) function	rocsparse_scsr2csc_rank_0 (handle, m, n, nnz, csr_val, csr_row_ptr, csr_col_ind, csc_val, csc_row_ind, csc_col_ptr, copy_values, idx_base, temp_buffer)

integer(kind(rocsparse_status_success)) function	rocsparse_scsr2csc_rank_1 (handle, m, n, nnz, csr_val, csr_row_ptr, csr_col_ind, csc_val, csc_row_ind, csc_col_ptr, copy_values, idx_base, temp_buffer)

Detailed Description

Convert a sparse CSR matrix into a sparse CSC matrix.

rocsparse_csr2csc converts a CSR matrix into a CSC matrix. The resulting matrix can also be seen as the transpose of the input matrix. rocsparse_csr2csc can also be used to convert a CSC matrix into a CSR matrix.

The conversion of a sparse matrix from CSR to CSC format involves two steps. First, call rocsparse_csr2csc_buffer_size to determine the size of the required tempory storage buffer. Then allocate this buffer. Secondly, call rocsparse_csr2csc to complete the conversion. After the conversion is complete, free the temporary buffer.

Both rocsparse_csr2csc_buffer_size and rocsparse_csr2csc take a rocsparse_action parameter as input. This copy_values parameter decides whether csc_row_ind and csc_val are filled during conversion (rocsparse_action_numeric) or whether only csc_row_ind is filled (rocsparse_action_symbolic). Using rocsparse_action_symbolic can be useful, for example, if only the sparsity pattern is required.

Note: This function is non-blocking and executed asynchronously with respect to the host. It can return before the actual computation has finished.; This routine supports execution in a hipGraph context.

Parameters

[in]	handle	- handle to the rocSPARSE library context queue.
[in]	m	- number of rows of the sparse CSR matrix.
[in]	n	- number of columns of the sparse CSR matrix.
[in]	nnz	- number of non-zero entries of the sparse CSR matrix.
[in]	csr_val	- array of `nnz` elements of the sparse CSR matrix.
[in]	csr_row_ptr	- array of `m+1` elements that point to the start of every row of the sparse CSR matrix.
[in]	csr_col_ind	- array of `nnz` elements containing the column indices of the sparse CSR matrix.
[out]	csc_val	- array of `nnz` elements of the sparse CSC matrix.
[out]	csc_row_ind	- array of `nnz` elements containing the row indices of the sparse CSC matrix.
[out]	csc_col_ptr	- array of `n+1` elements that point to the start of every column of the sparse CSC matrix.
[in]	copy_values	- `rocsparse_action_symbolic` or `rocsparse_action_numeric`.
[in]	idx_base	- `rocsparse_index_base_zero` or `rocsparse_index_base_one`.
[in]	temp_buffer	- temporary storage buffer allocated by the user. The size is returned by rocsparse_csr2csc_buffer_size().

Return values

rocsparse_status_success	the operation completed successfully.
rocsparse_status_invalid_handle	the library context was not initialized.
rocsparse_status_invalid_size	`m`, `n`, or `nnz` is invalid.
rocsparse_status_invalid_pointer	`csr_val`, `csr_row_ptr`, `csr_col_ind`, `csc_val`, `csc_row_ind`, `csc_col_ptr`, or `temp_buffer` pointer is invalid.
rocsparse_status_arch_mismatch	the device is not supported.
rocsparse_status_internal_error	an internal error occurred.

Example: This example computes the transpose of a CSR matrix.
// 1 2 0 3 0

// A = 0 4 5 0 0

// 6 0 0 7 8

rocsparse_int m_A = 3;

rocsparse_int n_A = 5;

rocsparse_int nnz_A = 8;

csr_row_ptr_A[m_A + 1] = {0, 3, 5, 8}; // device memory

csr_col_ind_A[nnz_A] = {0, 1, 3, 1, 2, 0, 3, 4}; // device memory

csr_val_A[nnz_A] = {1, 2, 3, 4, 5, 6, 7, 8}; // device memory

// Allocate memory for transposed CSR matrix

rocsparse_int m_T = n_A;

rocsparse_int n_T = m_A;

rocsparse_int nnz_T = nnz_A;

rocsparse_int* csr_row_ptr_T;

rocsparse_int* csr_col_ind_T;

float* csr_val_T;

hipMalloc((void**)&csr_row_ptr_T, sizeof(rocsparse_int) * (m_T + 1));

hipMalloc((void**)&csr_col_ind_T, sizeof(rocsparse_int) * nnz_T);

hipMalloc((void**)&csr_val_T, sizeof(float) * nnz_T);

// Obtain the temporary buffer size

size_t buffer_size;

rocsparse_csr2csc_buffer_size(handle,

m_A,

n_A,

nnz_A,

csr_row_ptr_A,

csr_col_ind_A,

rocsparse_action_numeric,

&buffer_size);

// Allocate temporary buffer

void* temp_buffer;

hipMalloc(&temp_buffer, buffer_size);

rocsparse_scsr2csc(handle,

m_A,

n_A,

nnz_A,

csr_val_A,

csr_row_ptr_A,

csr_col_ind_A,

csr_val_T,

csr_col_ind_T,

csr_row_ptr_T,

rocsparse_action_numeric,

rocsparse_index_base_zero,

temp_buffer);

hipfort_rocsparse_enums::rocsparse_index_base_zero
@ rocsparse_index_base_zero
Definition hipfort_rocsparse_enums.F90:42

hipfort_rocsparse_enums::rocsparse_action_numeric
@ rocsparse_action_numeric
Definition hipfort_rocsparse_enums.F90:75

Example: This example computes the symbolic transpose of A

Member Function/Subroutine Documentation