strco

NAME

strco - (obsolete) estimate the condition number of a triangular matrix A. It is typical to follow a call to STRCO with a call to STRSL to solve Ax = b or to STRDI to compute the determinant and inverse of A.

SYNOPSIS

  SUBROUTINE STRCO( A, LDA, N, RCOND, WORK, JOB)
  INTEGER LDA, N, JOB
  REAL RCOND
  REAL A(LDA,*), WORK(*)
 
  SUBROUTINE STRCO_64( A, LDA, N, RCOND, WORK, JOB)
  INTEGER*8 LDA, N, JOB
  REAL RCOND
  REAL A(LDA,*), WORK(*)

C INTERFACE

#include <sunperf.h>

void strco(float *a, int lda, int n, float *rcond, int job);

void strco_64(float *a, long lda, long n, float *rcond, long job);

ARGUMENTS

* A (input/output): Matrix A.
* LDA (input): Leading dimension of the array A as specified in a dimension or type statement. LDA >= max(1,N).
* N (input): Order of the matrix A. N >= 0.
* RCOND (output): On exit, an estimate of the reciprocal condition number of A. 0.0 <= RCOND <= 1.0. As the value of RCOND gets smaller, operations with A such as solving Ax = b may become less stable. If RCOND satisfies RCOND + 1.0 = 1.0 then A may be singular to working precision.
* WORK (workspace): Scratch array with a dimension of N.
* JOB (input): If JOB = 0, then A is lower triangular; otherwise A is upper triangular.