(S|D)LASQ1

Single and double LASQ1.

Description

Computes the singular values of a square bidiagonal matrix to high relative accuracy.

LAPACK Interface

void slasq1(const qml_long *N, float *D, float *E, float *WORK, qml_long *INFO);

void dlasq1(const qml_long *N, double *D, double *E, double *WORK, qml_long *INFO);

Arguments

N	Number of rows and columns of matrix A
D	Vector of diagonal elements of A of length N, overwritten by sorted singular values on exit
E	Vector of off-diagonal elements of A of length N - 1, destroyed on exit
WORK	Work space of size 4N
INFO	0 on success, <0 for bad arguments, >0 if no convergence