DGET04 computes the difference between a computed solution and the


 true solution to a system of linear equations.


 RESID =  ( norm(X-XACT) * RCOND ) / ( norm(XACT) * EPS ),


 where RCOND is the reciprocal of the condition number and EPS is the


 machine epsilon.

N

          N is INTEGER


          The number of rows of the matrices X and XACT.  N >= 0.

NRHS

          NRHS is INTEGER


          The number of columns of the matrices X and XACT.  NRHS >= 0.

X

          X is DOUBLE PRECISION array, dimension (LDX,NRHS)


          The computed solution vectors.  Each vector is stored as a


          column of the matrix X.

LDX

          LDX is INTEGER


          The leading dimension of the array X.  LDX >= max(1,N).

XACT

          XACT is DOUBLE PRECISION array, dimension( LDX, NRHS )


          The exact solution vectors.  Each vector is stored as a


          column of the matrix XACT.

LDXACT

          LDXACT is INTEGER


          The leading dimension of the array XACT.  LDXACT >= max(1,N).

RCOND

          RCOND is DOUBLE PRECISION


          The reciprocal of the condition number of the coefficient


          matrix in the system of equations.

RESID

          RESID is DOUBLE PRECISION


          The maximum over the NRHS solution vectors of


          ( norm(X-XACT) * RCOND ) / ( norm(XACT) * EPS )

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