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oneapi::mkl::sparse::gemv
Computes a sparse matrix-dense vector product.
Description
The oneapi::mkl::sparse::gemv routine computes a sparse matrix-dense vector product defined as
 
   where 
 and 
 are scalars, 
 is a general sparse matrix of dimensions num_rows rows and num_cols columns and 
 is a matrix modifier:
 
   The dense vectors 
 and 
 are appropriately sized based on matrix product dimensions of 
.
API
Syntax
Using SYCL buffers:
namespace oneapi::mkl::sparse {
    void gemv (
        sycl::queue &queue,
        oneapi::mkl::transpose transpose_flag,
        const DATA_TYPE alpha,
        oneapi::mkl::sparse::matrix_handle_t handle,
        sycl::buffer<DATA_TYPE, 1> &x,
        const DATA_TYPE beta,
        sycl::buffer<DATA_TYPE, 1> &y)
} 
   Using USM pointers:
namespace oneapi::mkl::sparse {
    sycl::event gemv (
        sycl::queue &queue,
        oneapi::mkl::transpose transpose_flag,
        const DATA_TYPE alpha,
        oneapi::mkl::sparse::matrix_handle_t handle,
        const DATA_TYPE *x,
        DATA_TYPE beta,
        DATA_TYPE *y,
        const std::vector<sycl::event> &dependencies= {})
} 
    
   Include Files
oneapi/mkl/spblas.hpp
Input Parameters
- queue
 -  
     
Specifies the SYCL command queue which will be used for SYCL kernels execution.
 - transpose_flag
 -  
     
Specifies operation op() on input matrix.
oneapi::mkl::transpose::nontrans
Non-transpose,
.oneapi::mkl::transpose::trans
Transpose,
.oneapi::mkl::transpose::conjtrans
Conjugate transpose,
.NOTE:Currently, the only supported case for operation is oneapi::mkl::transpose::nontrans. - alpha
 -  
     
Specifies the scalar,
. - handle
 -  
     
Handle to object containing sparse matrix and other internal data. Created using one of the oneapi::mkl::sparse::set_<sparse_matrix_type>_data routines.
NOTE:Currently, the only supported case for <sparse_matrix_type> is csr. - x
 -  
     
SYCL buffer or device-accessible USM pointer of size at least equal to the number of columns of input matrix if transpse_flag = oneapi::mkl::transpose::nontrans and at least the number of rows of input matrix otherwise.
 - beta
 -  
     
Specifies the scalar,
. - y
 -  
     
SYCL buffer or device-accessible USM pointer of size at least equal to the number of rows of the input matrix if transpose_flag = oneapi::mkl::transpose::nontrans and at least the number of columns of the input matrix otherwise.
 - dependencies
 -  
     
A vector of type std::vector<sycl::event> containing the list of events that the oneapi::mkl::sparse::gemv routine depends on.
 
Output Parameters
- y
 -  
     
Overwritten by the updated vector
. 
Return Values (USM Only)
- sycl::event
 -  
     
SYCL event which can be waited upon or added as a dependency for the completion of the gemv routine.
 
Examples
An example of how to use oneapi::mkl::sparse::gemv with SYCL buffers or USM pointers can be found in the oneMKL installation directory, under:
examples/dpcpp/sparse_blas/source/sparse_gemv.cpp
examples/dpcpp/sparse_blas/source/sparse_gemv_usm.cpp