*> \brief \b DLAG2S converts a double precision matrix to a single precision matrix. * * =========== DOCUMENTATION =========== * * Online html documentation available at * http://www.netlib.org/lapack/explore-html/ * *> \htmlonly *> Download DLAG2S + dependencies *> *> [TGZ] *> *> [ZIP] *> *> [TXT] *> \endhtmlonly * * Definition: * =========== * * SUBROUTINE DLAG2S( M, N, A, LDA, SA, LDSA, INFO ) * * .. Scalar Arguments .. * INTEGER INFO, LDA, LDSA, M, N * .. * .. Array Arguments .. * REAL SA( LDSA, * ) * DOUBLE PRECISION A( LDA, * ) * .. * * *> \par Purpose: * ============= *> *> \verbatim *> *> DLAG2S converts a DOUBLE PRECISION matrix, SA, to a SINGLE *> PRECISION matrix, A. *> *> RMAX is the overflow for the SINGLE PRECISION arithmetic *> DLAG2S checks that all the entries of A are between -RMAX and *> RMAX. If not the conversion is aborted and a flag is raised. *> *> This is an auxiliary routine so there is no argument checking. *> \endverbatim * * Arguments: * ========== * *> \param[in] M *> \verbatim *> M is INTEGER *> The number of lines of the matrix A. M >= 0. *> \endverbatim *> *> \param[in] N *> \verbatim *> N is INTEGER *> The number of columns of the matrix A. N >= 0. *> \endverbatim *> *> \param[in] A *> \verbatim *> A is DOUBLE PRECISION array, dimension (LDA,N) *> On entry, the M-by-N coefficient matrix A. *> \endverbatim *> *> \param[in] LDA *> \verbatim *> LDA is INTEGER *> The leading dimension of the array A. LDA >= max(1,M). *> \endverbatim *> *> \param[out] SA *> \verbatim *> SA is REAL array, dimension (LDSA,N) *> On exit, if INFO=0, the M-by-N coefficient matrix SA; if *> INFO>0, the content of SA is unspecified. *> \endverbatim *> *> \param[in] LDSA *> \verbatim *> LDSA is INTEGER *> The leading dimension of the array SA. LDSA >= max(1,M). *> \endverbatim *> *> \param[out] INFO *> \verbatim *> INFO is INTEGER *> = 0: successful exit. *> = 1: an entry of the matrix A is greater than the SINGLE *> PRECISION overflow threshold, in this case, the content *> of SA in exit is unspecified. *> \endverbatim * * Authors: * ======== * *> \author Univ. of Tennessee *> \author Univ. of California Berkeley *> \author Univ. of Colorado Denver *> \author NAG Ltd. * *> \date December 2016 * *> \ingroup doubleOTHERauxiliary * * ===================================================================== SUBROUTINE DLAG2S( M, N, A, LDA, SA, LDSA, INFO ) * * -- LAPACK auxiliary routine (version 3.7.0) -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- * December 2016 * * .. Scalar Arguments .. INTEGER INFO, LDA, LDSA, M, N * .. * .. Array Arguments .. REAL SA( LDSA, * ) DOUBLE PRECISION A( LDA, * ) * .. * * ===================================================================== * * .. Local Scalars .. INTEGER I, J DOUBLE PRECISION RMAX * .. * .. External Functions .. REAL SLAMCH EXTERNAL SLAMCH * .. * .. Executable Statements .. * RMAX = SLAMCH( 'O' ) DO 20 J = 1, N DO 10 I = 1, M IF( ( A( I, J ).LT.-RMAX ) .OR. ( A( I, J ).GT.RMAX ) ) THEN INFO = 1 GO TO 30 END IF SA( I, J ) = A( I, J ) 10 CONTINUE 20 CONTINUE INFO = 0 30 CONTINUE RETURN * * End of DLAG2S * END