XLPack 6.1
Excel VBA Numerical Library Reference Manual
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◆ Zspr()

Sub Zspr ( Uplo As  String,
N As  Long,
Alpha As  Complex,
X_I As  Complex,
Ap_I As  Complex,
Optional IncX As  Long = 1 
)

Rank 1 operation: A <- αxxT + A (complex symmetric matrices in packed form) (BLAS 2)

Purpose
This routine performs the symmetric rank 1 operation
A <- αxx^T + A
where α is a complex scalar, x is an n element vector and A is an n x n symmetric matrix, supplied in packed form.
Parameters
[in]uploSpecifies whether the upper or lower triangular part of the matrix A is supplied in the packed array Ap() as follows:
= "U": The upper triangular part of A is supplied in Ap().
= "L": The lower triangular part of A is supplied in Ap().
[in]NOrder of the matrix A. (N >= 0) (If N = 0, returns without computation)
[in]AlphaScalar α.
[in]X_IAn element X(I) of the array X(). Starting from this location, vector x is stored with element spacing IncX.
[in]Ap_IAn element Ap(I) of the array Ap().
[in] Starting from this location, N x N symmetric matrix A is stored in packed form. According to Uplo, only upper or lower triangular part is to be referenced.
[out] Starting from this location, N x N symmetric matrix αxx^T + A is stored in packed form. According to Uplo, only upper or lower triangular part is stored.
[in]IncX(Optional)
Element spacing of vector x in the array X(). (IncX <> 0) (default = 1)
Reference
BLAS