dqrt12.f3

Usage

Functions/Subroutines

double precision function dqrt12 (m, n, a, lda, s, work, lwork)
DQRT12

Function/Subroutine Documentation

double precision function dqrt12 (integer m, integer n, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( * ) s, double precision, dimension( lwork ) work, integer lwork)

DQRT12

Purpose:

!>
!> DQRT12 computes the singular values `svlues' of the upper trapezoid
!> of A(1:M,1:N) and returns the ratio
!>
!>      || svlues - s ||/(||s||*eps*max(M,N))
!>

Parameters

!>          M is INTEGER
!>          The number of rows of the matrix A.
!>

!>          N is INTEGER
!>          The number of columns of the matrix A.
!>

!>          A is DOUBLE PRECISION array, dimension (LDA,N)
!>          The M-by-N matrix A. Only the upper trapezoid is referenced.
!>

LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.
!>

!>          S is DOUBLE PRECISION array, dimension (min(M,N))
!>          The singular values of the matrix A.
!>

WORK

!>          WORK is DOUBLE PRECISION array, dimension (LWORK)
!>

LWORK

!>          LWORK is INTEGER
!>          The length of the array WORK. LWORK >= max(M*N + 4*min(M,N) +
!>          max(M,N), M*N+2*MIN( M, N )+4*N).
!>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 88 of file dqrt12.f.