HP MLIB User's Guide Vol. 1 7th Ed.

396 HP MLIB User’s Guide
F_SSYR2/F_DSYR2/F_CSYR2/F_ZSYR2 Symmetric rank-2 update
Y REAL or COMPLEX array, minimum length
(N - 1) x |incy| + 1.
INCY Increment for the array y. A vector y having component
y
i
, i = 1,..., n, is stored in an array Y() with increment
argument incy. If incy > 0 then y
i
is stored in
Y(1 + (i - 1) x incy). If incy < 0 then y
i
is stored in
Y(1 + (N - i) x |incy|). incy = 0 is an illegal value.
BETA The scalar BETA.
A REAL or COMPLEX array, dimension (LDA, N).
LDA Leading dimension of array A. If lda < 1 or lda < n, an
error condition is generated.
Output A The upper or lower triangle of the updated A matrix, as
specified by uplo, replaces the upper or lower triangle
of the input, respectively. The other triangle of A is
unchanged.
A αxy
T
αyx
T
βA with A=A
T
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