*> \brief \b CGET10 * * =========== DOCUMENTATION =========== * * Online html documentation available at * http://www.netlib.org/lapack/explore-html/ * * Definition: * =========== * * SUBROUTINE CGET10( M, N, A, LDA, B, LDB, WORK, RWORK, RESULT ) * * .. Scalar Arguments .. * INTEGER LDA, LDB, M, N * REAL RESULT * .. * .. Array Arguments .. * REAL RWORK( * ) * COMPLEX A( LDA, * ), B( LDB, * ), WORK( * ) * .. * * *> \par Purpose: * ============= *> *> \verbatim *> *> CGET10 compares two matrices A and B and computes the ratio *> RESULT = norm( A - B ) / ( norm(A) * M * EPS ) *> \endverbatim * * Arguments: * ========== * *> \param[in] M *> \verbatim *> M is INTEGER *> The number of rows of the matrices A and B. *> \endverbatim *> *> \param[in] N *> \verbatim *> N is INTEGER *> The number of columns of the matrices A and B. *> \endverbatim *> *> \param[in] A *> \verbatim *> A is COMPLEX array, dimension (LDA,N) *> The m by n matrix A. *> \endverbatim *> *> \param[in] LDA *> \verbatim *> LDA is INTEGER *> The leading dimension of the array A. LDA >= max(1,M). *> \endverbatim *> *> \param[in] B *> \verbatim *> B is COMPLEX array, dimension (LDB,N) *> The m by n matrix B. *> \endverbatim *> *> \param[in] LDB *> \verbatim *> LDB is INTEGER *> The leading dimension of the array B. LDB >= max(1,M). *> \endverbatim *> *> \param[out] WORK *> \verbatim *> WORK is COMPLEX array, dimension (M) *> \endverbatim *> *> \param[out] RWORK *> \verbatim *> RWORK is COMPLEX array, dimension (M) *> \endverbatim *> *> \param[out] RESULT *> \verbatim *> RESULT is REAL *> RESULT = norm( A - B ) / ( norm(A) * M * EPS ) *> \endverbatim * * Authors: * ======== * *> \author Univ. of Tennessee *> \author Univ. of California Berkeley *> \author Univ. of Colorado Denver *> \author NAG Ltd. * *> \date November 2011 * *> \ingroup complex_eig * * ===================================================================== SUBROUTINE CGET10( M, N, A, LDA, B, LDB, WORK, RWORK, RESULT ) * * -- LAPACK test routine (version 3.4.0) -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- * November 2011 * * .. Scalar Arguments .. INTEGER LDA, LDB, M, N REAL RESULT * .. * .. Array Arguments .. REAL RWORK( * ) COMPLEX A( LDA, * ), B( LDB, * ), WORK( * ) * .. * * ===================================================================== * * .. Parameters .. REAL ONE, ZERO PARAMETER ( ONE = 1.0E+0, ZERO = 0.0E+0 ) * .. * .. Local Scalars .. INTEGER J REAL ANORM, EPS, UNFL, WNORM * .. * .. External Functions .. REAL SCASUM, SLAMCH, CLANGE EXTERNAL SCASUM, SLAMCH, CLANGE * .. * .. External Subroutines .. EXTERNAL CAXPY, CCOPY * .. * .. Intrinsic Functions .. INTRINSIC MAX, MIN, REAL * .. * .. Executable Statements .. * * Quick return if possible * IF( M.LE.0 .OR. N.LE.0 ) THEN RESULT = ZERO RETURN END IF * UNFL = SLAMCH( 'Safe minimum' ) EPS = SLAMCH( 'Precision' ) * WNORM = ZERO DO 10 J = 1, N CALL CCOPY( M, A( 1, J ), 1, WORK, 1 ) CALL CAXPY( M, CMPLX( -ONE ), B( 1, J ), 1, WORK, 1 ) WNORM = MAX( WNORM, SCASUM( N, WORK, 1 ) ) 10 CONTINUE * ANORM = MAX( CLANGE( '1', M, N, A, LDA, RWORK ), UNFL ) * IF( ANORM.GT.WNORM ) THEN RESULT = ( WNORM / ANORM ) / ( M*EPS ) ELSE IF( ANORM.LT.ONE ) THEN RESULT = ( MIN( WNORM, M*ANORM ) / ANORM ) / ( M*EPS ) ELSE RESULT = MIN( WNORM / ANORM, REAL( M ) ) / ( M*EPS ) END IF END IF * RETURN * * End of CGET10 * END