Visible to Intel only — GUID: GUID-6FBAD81F-C0A3-43C6-B66D-C0200D1C187B
Visible to Intel only — GUID: GUID-6FBAD81F-C0A3-43C6-B66D-C0200D1C187B
?symv
Computes a matrix-vector product for a complex symmetric matrix.
Syntax
call csymv( uplo, n, alpha, a, lda, x, incx, beta, y, incy )
call zsymv( uplo, n, alpha, a, lda, x, incx, beta, y, incy )
Include Files
- mkl.fi
Description
The routine performs the matrix-vector operation defined as
y := alpha*a*x + beta*y,
where:
alpha and beta are complex scalars
x and y are n-element complex vectors
a is an n-by-n symmetric complex matrix.
These routines have their real equivalents in BLAS (see ?symv in Chapter "BLAS and Sparse BLAS Routines").
Input Parameters
- uplo
-
CHARACTER*1. Specifies whether the upper or lower triangular part of the array a is used:
If uplo = 'U' or 'u', then the upper triangular part of the array a is used.
If uplo = 'L' or 'l', then the lower triangular part of the array a is used.
- n
-
INTEGER. Specifies the order of the matrix a. The value of n must be at least zero.
- alpha, beta
-
COMPLEX for csymv
DOUBLE COMPLEX for zsymv
Specify the scalars alpha and beta. When beta is supplied as zero, then y need not be set on input.
- a
-
COMPLEX for csymv
DOUBLE COMPLEX for zsymv
Array, DIMENSION (lda, n). Before entry with uplo = 'U' or 'u', the leading n-by-n upper triangular part of the array a must contain the upper triangular part of the symmetric matrix and the strictly lower triangular part of a is not referenced. Before entry with uplo = 'L' or 'l', the leading n-by-n lower triangular part of the array a must contain the lower triangular part of the symmetric matrix and the strictly upper triangular part of a is not referenced.
- lda
-
INTEGER. Specifies the leading dimension of A as declared in the calling (sub)program. The value of lda must be at least max(1,n).
- x
-
COMPLEX for csymv
DOUBLE COMPLEX for zsymv
Array, DIMENSION at least (1 + (n - 1)*abs(incx)). Before entry, the incremented array x must contain the n-element vector x.
- incx
-
INTEGER. Specifies the increment for the elements of x. The value of incx must not be zero.
- y
-
COMPLEX for csymv
DOUBLE COMPLEX for zsymv
Array, DIMENSION at least (1 + (n - 1)*abs(incy)). Before entry, the incremented array y must contain the n-element vector y.
- incy
-
INTEGER. Specifies the increment for the elements of y. The value of incy must not be zero.
Output Parameters
- y
-
Overwritten by the updated vector y.