dqrt14.f3

!>
!> DQRT14 checks whether X is in the row space of A or A'.  It does so
!> by scaling both X and A such that their norms are in the range
!> [sqrt(eps), 1/sqrt(eps)], then computing a QR factorization of [A,X]
!> (if TRANS = 'T') or an LQ factorization of [A',X]' (if TRANS = 'N'),
!> and returning the norm of the trailing triangle, scaled by
!> MAX(M,N,NRHS)*eps.
!> 

TRANS

!>          TRANS is CHARACTER*1
!>          = 'N':  No transpose, check for X in the row space of A
!>          = 'T':  Transpose, check for X in the row space of A'.
!> 

M

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

N

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

NRHS

!>          NRHS is INTEGER
!>          The number of right hand sides, i.e., the number of columns
!>          of X.
!> 

A

!>          A is DOUBLE PRECISION array, dimension (LDA,N)
!>          The M-by-N matrix A.
!> 

LDA

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

X

!>          X is DOUBLE PRECISION array, dimension (LDX,NRHS)
!>          If TRANS = 'N', the N-by-NRHS matrix X.
!>          IF TRANS = 'T', the M-by-NRHS matrix X.
!> 

LDX

!>          LDX is INTEGER
!>          The leading dimension of the array X.
!> 

WORK

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

LWORK

!>          LWORK is INTEGER
!>          length of workspace array required
!>          If TRANS = 'N', LWORK >= (M+NRHS)*(N+2);
!>          if TRANS = 'T', LWORK >= (N+NRHS)*(M+2).
!> 

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