csc_dusmm csc_dusmv csc_dussm csc_dussv csr_dusmm csr_dusmv csr_dussm csr_dussv ssc_dusmv ssr_dusmv

csr_dusmv() void csr_dusmv ( char  trans, int  m, int  n, double  alpha, const double  val[], const int  rowptr[], const int  colind[], int  base, const double  x[], int  incx, double  beta, double  y[], int  incy, int *  info  ) y <- αAx + βy or y <- αATx + βy (CSR) Purpose This function performs one of the following matrix-vector operations for a sparse matrix in CSR format. y <- αAx + βy or y <- αA^Tx + βy where alpha and beta are scalars, x and y are vectors and A is an m x n sparse matrix. Parameters [in] trans Specifies the operation to be performed. = 'N': y <- y <- αAx + βy. = 'T' or 'C': y <- αA^Tx + βy. [in] m Number of rows of matrix A. (m >= 0) (If m = 0, returns without computation) [in] n Number of columns of matrix A. (n >= 0) (If n = 0, returns without computation) [in] alpha Scalar α [in] val[] Array val[lval] (lval >= nnz) Values of nonzero elements of matrix A (where nnz is the number of nonzero elements). [in] rowptr[] Array rowptr[lrowptr] (lrowptr >= m + 1) Row pointers of matrix A. [in] colind[] Array colind[lcolind] (lcolind >= nnz) Column indices of matrix A (where nnz is the number of nonzero elements). [in] base Indexing of rowptr[] and colind[]. = 0: Zero-based (C style) indexing: Starting index is 0. = 1: One-based (Fortran style) indexing: Starting index is 1. [in] x[] Array x[lx] (lx >= 1 + (n - 1)*|incx| (trans = 'N'), lx >= 1 + (m - 1)*|incx| (trans = 'T' or 'C')) Vector x. [in] incx Storage spacing between elements of x[]. [in] beta Scalar β. [in,out] y[] Array y[ly] (ly >= 1 + (m - 1)*|incy| (trans = 'N'), ly >= 1 + (n - 1)*|incy| (trans = 'T' or 'C')) [in] Input vector y (If beta is supplied as zero, y[] needs not be set on input). [out] Output vector. (= αAx + βy) [in] incy Storage spacing between elements of y[]. [out] info = 0: Successful exit. = i < 0: The (-i)-th argument is invalid.