XLPack 7.0
XLPack Numerical Library (C API) Reference Manual
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◆ zspr()

void zspr ( char  uplo,
int  n,
doublecomplex  alpha,
doublecomplex  x[],
int  incx,
doublecomplex  ap[] 
)

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

Purpose
This routine performs the symmetric rank 1 operation
A <- alpha*x*x^T + A
where alpha 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 alpha.
[in]x[]Array x[lx] (lx >= 1 + (n - 1)*abs(incx))
Vector x.
[in]incxStorage spacing between elements of x. (incx != 0)
[in,out]ap[]Array ap[lap] (lap >= n(n + 1)/2)
[in] n x n symmetric matrix A in packed form. (Upper or lower triangle)
[out] Output matrix in packed form. (= alpha*x*x^T + A) (Upper or lower triangle)
Reference
BLAS