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Annotation of rpl/lapack/lapack/dlag2s.f, revision 1.10

1.10    ! bertrand    1: *> \brief \b DLAG2S
        !             2: *
        !             3: *  =========== DOCUMENTATION ===========
        !             4: *
        !             5: * Online html documentation available at 
        !             6: *            http://www.netlib.org/lapack/explore-html/ 
        !             7: *
        !             8: *> \htmlonly
        !             9: *> Download DLAG2S + dependencies 
        !            10: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlag2s.f"> 
        !            11: *> [TGZ]</a> 
        !            12: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlag2s.f"> 
        !            13: *> [ZIP]</a> 
        !            14: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlag2s.f"> 
        !            15: *> [TXT]</a>
        !            16: *> \endhtmlonly 
        !            17: *
        !            18: *  Definition:
        !            19: *  ===========
        !            20: *
        !            21: *       SUBROUTINE DLAG2S( M, N, A, LDA, SA, LDSA, INFO )
        !            22: * 
        !            23: *       .. Scalar Arguments ..
        !            24: *       INTEGER            INFO, LDA, LDSA, M, N
        !            25: *       ..
        !            26: *       .. Array Arguments ..
        !            27: *       REAL               SA( LDSA, * )
        !            28: *       DOUBLE PRECISION   A( LDA, * )
        !            29: *       ..
        !            30: *  
        !            31: *
        !            32: *> \par Purpose:
        !            33: *  =============
        !            34: *>
        !            35: *> \verbatim
        !            36: *>
        !            37: *> DLAG2S converts a DOUBLE PRECISION matrix, SA, to a SINGLE
        !            38: *> PRECISION matrix, A.
        !            39: *>
        !            40: *> RMAX is the overflow for the SINGLE PRECISION arithmetic
        !            41: *> DLAG2S checks that all the entries of A are between -RMAX and
        !            42: *> RMAX. If not the convertion is aborted and a flag is raised.
        !            43: *>
        !            44: *> This is an auxiliary routine so there is no argument checking.
        !            45: *> \endverbatim
        !            46: *
        !            47: *  Arguments:
        !            48: *  ==========
        !            49: *
        !            50: *> \param[in] M
        !            51: *> \verbatim
        !            52: *>          M is INTEGER
        !            53: *>          The number of lines of the matrix A.  M >= 0.
        !            54: *> \endverbatim
        !            55: *>
        !            56: *> \param[in] N
        !            57: *> \verbatim
        !            58: *>          N is INTEGER
        !            59: *>          The number of columns of the matrix A.  N >= 0.
        !            60: *> \endverbatim
        !            61: *>
        !            62: *> \param[in] A
        !            63: *> \verbatim
        !            64: *>          A is DOUBLE PRECISION array, dimension (LDA,N)
        !            65: *>          On entry, the M-by-N coefficient matrix A.
        !            66: *> \endverbatim
        !            67: *>
        !            68: *> \param[in] LDA
        !            69: *> \verbatim
        !            70: *>          LDA is INTEGER
        !            71: *>          The leading dimension of the array A.  LDA >= max(1,M).
        !            72: *> \endverbatim
        !            73: *>
        !            74: *> \param[out] SA
        !            75: *> \verbatim
        !            76: *>          SA is REAL array, dimension (LDSA,N)
        !            77: *>          On exit, if INFO=0, the M-by-N coefficient matrix SA; if
        !            78: *>          INFO>0, the content of SA is unspecified.
        !            79: *> \endverbatim
        !            80: *>
        !            81: *> \param[in] LDSA
        !            82: *> \verbatim
        !            83: *>          LDSA is INTEGER
        !            84: *>          The leading dimension of the array SA.  LDSA >= max(1,M).
        !            85: *> \endverbatim
        !            86: *>
        !            87: *> \param[out] INFO
        !            88: *> \verbatim
        !            89: *>          INFO is INTEGER
        !            90: *>          = 0:  successful exit.
        !            91: *>          = 1:  an entry of the matrix A is greater than the SINGLE
        !            92: *>                PRECISION overflow threshold, in this case, the content
        !            93: *>                of SA in exit is unspecified.
        !            94: *> \endverbatim
        !            95: *
        !            96: *  Authors:
        !            97: *  ========
        !            98: *
        !            99: *> \author Univ. of Tennessee 
        !           100: *> \author Univ. of California Berkeley 
        !           101: *> \author Univ. of Colorado Denver 
        !           102: *> \author NAG Ltd. 
        !           103: *
        !           104: *> \date November 2011
        !           105: *
        !           106: *> \ingroup doubleOTHERauxiliary
        !           107: *
        !           108: *  =====================================================================
1.1       bertrand  109:       SUBROUTINE DLAG2S( M, N, A, LDA, SA, LDSA, INFO )
                    110: *
1.10    ! bertrand  111: *  -- LAPACK auxiliary routine (version 3.4.0) --
1.1       bertrand  112: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
                    113: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
1.10    ! bertrand  114: *     November 2011
1.1       bertrand  115: *
                    116: *     .. Scalar Arguments ..
                    117:       INTEGER            INFO, LDA, LDSA, M, N
                    118: *     ..
                    119: *     .. Array Arguments ..
                    120:       REAL               SA( LDSA, * )
                    121:       DOUBLE PRECISION   A( LDA, * )
                    122: *     ..
                    123: *
1.8       bertrand  124: *  =====================================================================
1.1       bertrand  125: *
                    126: *     .. Local Scalars ..
                    127:       INTEGER            I, J
                    128:       DOUBLE PRECISION   RMAX
                    129: *     ..
                    130: *     .. External Functions ..
                    131:       REAL               SLAMCH
                    132:       EXTERNAL           SLAMCH
                    133: *     ..
                    134: *     .. Executable Statements ..
                    135: *
                    136:       RMAX = SLAMCH( 'O' )
                    137:       DO 20 J = 1, N
                    138:          DO 10 I = 1, M
                    139:             IF( ( A( I, J ).LT.-RMAX ) .OR. ( A( I, J ).GT.RMAX ) ) THEN
                    140:                INFO = 1
                    141:                GO TO 30
                    142:             END IF
                    143:             SA( I, J ) = A( I, J )
                    144:    10    CONTINUE
                    145:    20 CONTINUE
                    146:       INFO = 0
                    147:    30 CONTINUE
                    148:       RETURN
                    149: *
                    150: *     End of DLAG2S
                    151: *
                    152:       END