# cla_syrcond_x.f man page

cla_syrcond_x.f —

## Synopsis

### Functions/Subroutines

REAL functioncla_syrcond_x(UPLO, N, A, LDA, AF, LDAF, IPIV, X, INFO, WORK, RWORK)CLA_SYRCOND_Xcomputes the infinity norm condition number of op(A)*diag(x) for symmetric indefinite matrices.

## Function/Subroutine Documentation

### REAL function cla_syrcond_x (characterUPLO, integerN, complex, dimension( lda, * )A, integerLDA, complex, dimension( ldaf, * )AF, integerLDAF, integer, dimension( * )IPIV, complex, dimension( * )X, integerINFO, complex, dimension( * )WORK, real, dimension( * )RWORK)

**CLA_SYRCOND_X** computes the infinity norm condition number of op(A)*diag(x) for symmetric indefinite matrices.

**Purpose:**

```
CLA_SYRCOND_X Computes the infinity norm condition number of
op(A) * diag(X) where X is a COMPLEX vector.
```

**Parameters:**

*UPLO*

```
UPLO is CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
```

*N*

```
N is INTEGER
The number of linear equations, i.e., the order of the
matrix A. N >= 0.
```

*A*

```
A is COMPLEX array, dimension (LDA,N)
On entry, the N-by-N matrix A.
```

*LDA*

```
LDA is INTEGER
The leading dimension of the array A. LDA >= max(1,N).
```

*AF*

```
AF is COMPLEX array, dimension (LDAF,N)
The block diagonal matrix D and the multipliers used to
obtain the factor U or L as computed by CSYTRF.
```

*LDAF*

```
LDAF is INTEGER
The leading dimension of the array AF. LDAF >= max(1,N).
```

*IPIV*

```
IPIV is INTEGER array, dimension (N)
Details of the interchanges and the block structure of D
as determined by CSYTRF.
```

*X*

```
X is COMPLEX array, dimension (N)
The vector X in the formula op(A) * diag(X).
```

*INFO*

```
INFO is INTEGER
= 0: Successful exit.
i > 0: The ith argument is invalid.
```

*WORK*

```
WORK is COMPLEX array, dimension (2*N).
Workspace.
```

*RWORK*

```
RWORK is REAL array, dimension (N).
Workspace.
```

**Author:**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

**Date:**

September 2012

Definition at line 131 of file cla_syrcond_x.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

cla_syrcond_x(3) is an alias of cla_syrcond_x.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK