BLAS/SRC/zgemv.f(3) Library Functions Manual BLAS/SRC/zgemv.f(3) NAME BLAS/SRC/zgemv.f SYNOPSIS Functions/Subroutines subroutine zgemv (trans, m, n, alpha, a, lda, x, incx, beta, y, incy) ZGEMV Function/Subroutine Documentation subroutine zgemv (character trans, integer m, integer n, complex*16 alpha, complex*16, dimension(lda,*) a, integer lda, complex*16, dimension(*) x, integer incx, complex*16 beta, complex*16, dimension(*) y, integer incy) ZGEMV Purpose: ZGEMV performs one of the matrix-vector operations y := alpha*A*x + beta*y, or y := alpha*A**T*x + beta*y, or y := alpha*A**H*x + beta*y, where alpha and beta are scalars, x and y are vectors and A is an m by n matrix. Parameters TRANS TRANS is CHARACTER*1 On entry, TRANS specifies the operation to be performed as follows: TRANS = 'N' or 'n' y := alpha*A*x + beta*y. TRANS = 'T' or 't' y := alpha*A**T*x + beta*y. TRANS = 'C' or 'c' y := alpha*A**H*x + beta*y. M M is INTEGER On entry, M specifies the number of rows of the matrix A. M must be at least zero. N N is INTEGER On entry, N specifies the number of columns of the matrix A. N must be at least zero. ALPHA ALPHA is COMPLEX*16 On entry, ALPHA specifies the scalar alpha. A A is COMPLEX*16 array, dimension ( LDA, N ) Before entry, the leading m by n part of the array A must contain the matrix of coefficients. LDA LDA is INTEGER On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA must be at least max( 1, m ). X X is COMPLEX*16 array, dimension at least ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N' or 'n' and at least ( 1 + ( m - 1 )*abs( INCX ) ) otherwise. Before entry, the incremented array X must contain the vector x. INCX INCX is INTEGER On entry, INCX specifies the increment for the elements of X. INCX must not be zero. BETA BETA is COMPLEX*16 On entry, BETA specifies the scalar beta. When BETA is supplied as zero then Y need not be set on input. Y Y is COMPLEX*16 array, dimension at least ( 1 + ( m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n' and at least ( 1 + ( n - 1 )*abs( INCY ) ) otherwise. Before entry with BETA non-zero, the incremented array Y must contain the vector y. On exit, Y is overwritten by the updated vector y. If either m or n is zero, then Y not referenced and the function performs a quick return. INCY INCY is INTEGER On entry, INCY specifies the increment for the elements of Y. INCY must not be zero. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Further Details: Level 2 Blas routine. The vector and matrix arguments are not referenced when N = 0, or M = 0 -- Written on 22-October-1986. Jack Dongarra, Argonne National Lab. Jeremy Du Croz, Nag Central Office. Sven Hammarling, Nag Central Office. Richard Hanson, Sandia National Labs. Definition at line 159 of file zgemv.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 BLAS/SRC/zgemv.f(3)