LAPACK
3.4.2
LAPACK: Linear Algebra PACKage

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Functions/Subroutines  
subroutine  cspmv (UPLO, N, ALPHA, AP, X, INCX, BETA, Y, INCY) 
CSPMV computes a matrixvector product for complex vectors using a complex symmetric packed matrix 
subroutine cspmv  (  character  UPLO, 
integer  N,  
complex  ALPHA,  
complex, dimension( * )  AP,  
complex, dimension( * )  X,  
integer  INCX,  
complex  BETA,  
complex, dimension( * )  Y,  
integer  INCY  
) 
CSPMV computes a matrixvector product for complex vectors using a complex symmetric packed matrix
Download CSPMV + dependencies [TGZ] [ZIP] [TXT]CSPMV performs the matrixvector operation y := alpha*A*x + beta*y, where alpha and beta are scalars, x and y are n element vectors and A is an n by n symmetric matrix, supplied in packed form.
[in]  UPLO  UPLO is CHARACTER*1 On entry, UPLO specifies whether the upper or lower triangular part of the matrix A is supplied in the packed array AP as follows: UPLO = 'U' or 'u' The upper triangular part of A is supplied in AP. UPLO = 'L' or 'l' The lower triangular part of A is supplied in AP. Unchanged on exit. 
[in]  N  N is INTEGER On entry, N specifies the order of the matrix A. N must be at least zero. Unchanged on exit. 
[in]  ALPHA  ALPHA is COMPLEX On entry, ALPHA specifies the scalar alpha. Unchanged on exit. 
[in]  AP  AP is COMPLEX array, dimension at least ( ( N*( N + 1 ) )/2 ). Before entry, with UPLO = 'U' or 'u', the array AP must contain the upper triangular part of the symmetric matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 ) and a( 2, 2 ) respectively, and so on. Before entry, with UPLO = 'L' or 'l', the array AP must contain the lower triangular part of the symmetric matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 ) and a( 3, 1 ) respectively, and so on. Unchanged on exit. 
[in]  X  X is COMPLEX array, dimension at least ( 1 + ( N  1 )*abs( INCX ) ). Before entry, the incremented array X must contain the N element vector x. Unchanged on exit. 
[in]  INCX  INCX is INTEGER On entry, INCX specifies the increment for the elements of X. INCX must not be zero. Unchanged on exit. 
[in]  BETA  BETA is COMPLEX On entry, BETA specifies the scalar beta. When BETA is supplied as zero then Y need not be set on input. Unchanged on exit. 
[in,out]  Y  Y is COMPLEX array, dimension at least ( 1 + ( N  1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the n element vector y. On exit, Y is overwritten by the updated vector y. 
[in]  INCY  INCY is INTEGER On entry, INCY specifies the increment for the elements of Y. INCY must not be zero. Unchanged on exit. 
Definition at line 152 of file cspmv.f.