!>
!> SQRT16 computes the residual for a solution of a system of linear
!> equations  A*x = b  or  A'*x = b:
!>    RESID = norm(B - A*X) / ( max(m,n) * norm(A) * norm(X) * EPS ),
!> where EPS is the machine epsilon.
!> 

TRANS

!>          TRANS is CHARACTER*1
!>          Specifies the form of the system of equations:
!>          = 'N':  A *x = b
!>          = 'T':  A'*x = b, where A' is the transpose of A
!>          = 'C':  A'*x = b, where A' is the transpose of A
!> 

M

!>          M is INTEGER
!>          The number of rows of the matrix A.  M >= 0.
!> 

N

!>          N is INTEGER
!>          The number of columns of the matrix A.  N >= 0.
!> 

NRHS

!>          NRHS is INTEGER
!>          The number of columns of B, the matrix of right hand sides.
!>          NRHS >= 0.
!> 

A

!>          A is REAL array, dimension (LDA,N)
!>          The original M x N matrix A.
!> 

LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= max(1,M).
!> 

X

!>          X is REAL array, dimension (LDX,NRHS)
!>          The computed solution vectors for the system of linear
!>          equations.
!> 

LDX

!>          LDX is INTEGER
!>          The leading dimension of the array X.  If TRANS = 'N',
!>          LDX >= max(1,N); if TRANS = 'T' or 'C', LDX >= max(1,M).
!> 

B

!>          B is REAL array, dimension (LDB,NRHS)
!>          On entry, the right hand side vectors for the system of
!>          linear equations.
!>          On exit, B is overwritten with the difference B - A*X.
!> 

LDB

!>          LDB is INTEGER
!>          The leading dimension of the array B.  IF TRANS = 'N',
!>          LDB >= max(1,M); if TRANS = 'T' or 'C', LDB >= max(1,N).
!> 

RWORK

!>          RWORK is REAL array, dimension (M)
!> 

RESID

!>          RESID is REAL
!>          The maximum over the number of right hand sides of
!>          norm(B - A*X) / ( max(m,n) * norm(A) * norm(X) * EPS ).
!> 

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.