(S|D|C|Z)SYTRI¶

Single, double, single complex, and double complex SYTRI.

Description¶

Computes the inverse of a symmetric indefinite matrix using one of the following factorizations:

$\fvar{A} = \fvar{U} \mult \fvar{D} \mult \trans{\fvar{U}}$

$\fvar{A} = \fvar{L} \mult \fvar{D} \mult \trans{\fvar{L}}$

LAPACK Interface¶

void ssytri(const char *UPLO, const qml_long *N, float *A, const qml_long *LDA,
    qml_long *IPIV, float *WORK, qml_long *INFO);

void dsytri(const char *UPLO, const qml_long *N, double *A, const qml_long *LDA,
    qml_long *IPIV, double *WORK, qml_long *INFO);

void csytri(const char *UPLO, const qml_long *N, qml_single_complex *A,
    const qml_long *LDA, qml_long *IPIV, qml_single_complex *WORK,
    qml_long *INFO);

void zsytri(const char *UPLO, const qml_long *N, qml_double_complex *A,
    const qml_long *LDA, qml_long *IPIV, qml_double_complex *WORK,
    qml_long *INFO);

Arguments¶

UPLO	Set to ‘U’ for upper triangular factorization, ‘L’ for lower
N	Number of rows and columns of A
A	Matrix of size N x N containing block diagonal matrix D with multipliers, as output by SYTRF
LDA	Leading dimension of A
IPIV	Array of pivots of size N, as provided by SYTRF
WORK	Work space of size at least 2N
INFO	0 on success, <0 for bad arguments, >0 if singular