?la_syrcond_x

Syntax

FORTRAN 77:

call cla_syrcond_x( uplo, n, a, lda, af, ldaf, ipiv, x, info, work, rwork )

call zla_syrcond_x( uplo, n, a, lda, af, ldaf, ipiv, x, info, work, rwork )

Include Files

• FORTRAN 77: mkl_lapack.fi and mkl_lapack.h

Description

The function computes the infinity norm condition number of

op(A) * diag(x)

where the x is a COMPLEX vector for cla_syrcond_x and a DOUBLE COMPLEX vector for zla_syrcond_x.

Input Parameters

uplo

CHARACTER*1. Must be 'U' or 'L'.

Specifies the triangle of A to store:

If uplo = 'U', the upper triangle of A is stored,

If uplo = 'L', the lower triangle of A is stored.

n

INTEGER. The number of linear equations, that is, the order of the matrix A; n ≥ 0.

a

COMPLEX for cla_syrcond_c

DOUBLE COMPLEX for zla_syrcond_c

Array, DIMENSION (lda, *). On entry, the n-by-n matrix A. The second dimension of a must be at least max(1,n).

lda

INTEGER. The leading dimension of the array a. lda ≥ max(1,n).

af

COMPLEX for cla_syrcond_c

DOUBLE COMPLEX for zla_syrcond_c

Array, DIMENSION (ldaf, *). The block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ?sytrf. The second dimension of af must be at least max(1,n).

ldaf

INTEGER. The leading dimension of the array af. ldaf ≥ max(1,n).

ipiv

INTEGER.

Array with DIMENSION n. Details of the interchanges and the block structure of D as determined by ?sytrf.

x

COMPLEX for cla_syrcond_c

DOUBLE COMPLEX for zla_syrcond_c

Array x with DIMENSION n. The vector x in the formula

op(A) * inv(diag(x)).

work

COMPLEX for cla_syrcond_c

DOUBLE COMPLEX for zla_syrcond_c

Array DIMENSION 2*n. Workspace.

rwork

REAL for cla_syrcond_c

DOUBLE PRECISION for zla_syrcond_c

Array DIMENSION n. Workspace.

Output Parameters

info

INTEGER.

If info = 0, the execution is successful.

If i > 0, the i-th parameter is invalid.