TheRock/rocm-libraries/projects/hipsparse/library/include/internal/conversion/hipsparse_coo2csr.h

/*! \file */
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#ifndef HIPSPARSE_COO2CSR_H
#define HIPSPARSE_COO2CSR_H

#ifdef __cplusplus
extern "C" {
#endif

/*! \ingroup conv_module
*  \brief Convert a sparse COO matrix into a sparse CSR matrix.
*
*  \details
*  \p hipsparseXcoo2csr converts the COO array containing the row indices into a
*  CSR array of row offsets that point to the start of every row.
*  It is assumed that the COO row index array is sorted and that all arrays have been allocated
*  prior to calling \p hipsparseXcoo2csr.
*
*  For example, given the COO row indices array:
*  \f[
*    \begin{align}
*    \text{cooRowInd} &= \begin{bmatrix} 0 & 0 & 1 & 2 & 2 & 4 & 4 & 4 \end{bmatrix}
*    \end{align}
*  \f]
*
*  the resulting CSR row pointer array after calling \p hipsparseXcoo2csr is:
*  \f[
*    \begin{align}
*    \text{csrRowPtr} &= \begin{bmatrix} 0 & 2 & 3 & 5 & 8 \end{bmatrix}
*    \end{align}
*  \f]
*
*  \note This function can also be used to convert a COO array containing the column indices into
*  a CSC array of column offsets that point to the start of every column. In this case, it is
*  assumed that the COO column index array is sorted instead.
*
*  \note
*  This function is non-blocking and executed asynchronously with respect to the host.
*  It can return before the actual computation has finished.
*
*  @param[in]
*  handle      handle to the hipSPARSE library context queue.
*  @param[in]
*  cooRowInd   array of \p nnz elements containing the row indices of the sparse COO
*              matrix.
*  @param[in]
*  nnz         number of non-zero entries of the sparse CSR matrix. Must be non-negative.
*  @param[in]
*  m           number of rows of the sparse CSR matrix. Must be non-negative.
*  @param[out]
*  csrRowPtr   array of \p m+1 elements that point to the start of every row of the
*              sparse CSR matrix.
*  @param[in]
*  idxBase     index base. \ref HIPSPARSE_INDEX_BASE_ZERO for zero-based indexing or
*              \ref HIPSPARSE_INDEX_BASE_ONE for one-based indexing.
*
*  \retval HIPSPARSE_STATUS_SUCCESS the operation completed successfully.
*  \retval HIPSPARSE_STATUS_NOT_INITIALIZED \p handle is not initialized.
*  \retval HIPSPARSE_STATUS_INVALID_VALUE \p handle is nullptr, \p m or \p nnz is negative,
*          \p cooRowInd or \p csrRowPtr is nullptr when \p nnz is greater than zero, or
*          \p idxBase is neither \ref HIPSPARSE_INDEX_BASE_ZERO nor \ref HIPSPARSE_INDEX_BASE_ONE.
*/
HIPSPARSE_EXPORT
hipsparseStatus_t hipsparseXcoo2csr(hipsparseHandle_t    handle,
                                    const int*           cooRowInd,
                                    int                  nnz,
                                    int                  m,
                                    int*                 csrRowPtr,
                                    hipsparseIndexBase_t idxBase);

#ifdef __cplusplus
}
#endif

#endif /* HIPSPARSE_COO2CSR_H */