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    1: *> \brief \b ZLAG2C converts a complex double precision matrix to a complex single precision matrix.
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at
    6: *            http://www.netlib.org/lapack/explore-html/
    7: *
    8: *> \htmlonly
    9: *> Download ZLAG2C + dependencies
   10: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlag2c.f">
   11: *> [TGZ]</a>
   12: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlag2c.f">
   13: *> [ZIP]</a>
   14: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlag2c.f">
   15: *> [TXT]</a>
   16: *> \endhtmlonly
   17: *
   18: *  Definition:
   19: *  ===========
   20: *
   21: *       SUBROUTINE ZLAG2C( M, N, A, LDA, SA, LDSA, INFO )
   22: *
   23: *       .. Scalar Arguments ..
   24: *       INTEGER            INFO, LDA, LDSA, M, N
   25: *       ..
   26: *       .. Array Arguments ..
   27: *       COMPLEX            SA( LDSA, * )
   28: *       COMPLEX*16         A( LDA, * )
   29: *       ..
   30: *
   31: *
   32: *> \par Purpose:
   33: *  =============
   34: *>
   35: *> \verbatim
   36: *>
   37: *> ZLAG2C converts a COMPLEX*16 matrix, SA, to a COMPLEX matrix, A.
   38: *>
   39: *> RMAX is the overflow for the SINGLE PRECISION arithmetic
   40: *> ZLAG2C checks that all the entries of A are between -RMAX and
   41: *> RMAX. If not the conversion is aborted and a flag is raised.
   42: *>
   43: *> This is an auxiliary routine so there is no argument checking.
   44: *> \endverbatim
   45: *
   46: *  Arguments:
   47: *  ==========
   48: *
   49: *> \param[in] M
   50: *> \verbatim
   51: *>          M is INTEGER
   52: *>          The number of lines of the matrix A.  M >= 0.
   53: *> \endverbatim
   54: *>
   55: *> \param[in] N
   56: *> \verbatim
   57: *>          N is INTEGER
   58: *>          The number of columns of the matrix A.  N >= 0.
   59: *> \endverbatim
   60: *>
   61: *> \param[in] A
   62: *> \verbatim
   63: *>          A is COMPLEX*16 array, dimension (LDA,N)
   64: *>          On entry, the M-by-N coefficient matrix A.
   65: *> \endverbatim
   66: *>
   67: *> \param[in] LDA
   68: *> \verbatim
   69: *>          LDA is INTEGER
   70: *>          The leading dimension of the array A.  LDA >= max(1,M).
   71: *> \endverbatim
   72: *>
   73: *> \param[out] SA
   74: *> \verbatim
   75: *>          SA is COMPLEX array, dimension (LDSA,N)
   76: *>          On exit, if INFO=0, the M-by-N coefficient matrix SA; if
   77: *>          INFO>0, the content of SA is unspecified.
   78: *> \endverbatim
   79: *>
   80: *> \param[in] LDSA
   81: *> \verbatim
   82: *>          LDSA is INTEGER
   83: *>          The leading dimension of the array SA.  LDSA >= max(1,M).
   84: *> \endverbatim
   85: *>
   86: *> \param[out] INFO
   87: *> \verbatim
   88: *>          INFO is INTEGER
   89: *>          = 0:  successful exit.
   90: *>          = 1:  an entry of the matrix A is greater than the SINGLE
   91: *>                PRECISION overflow threshold, in this case, the content
   92: *>                of SA in exit is unspecified.
   93: *> \endverbatim
   94: *
   95: *  Authors:
   96: *  ========
   97: *
   98: *> \author Univ. of Tennessee
   99: *> \author Univ. of California Berkeley
  100: *> \author Univ. of Colorado Denver
  101: *> \author NAG Ltd.
  102: *
  103: *> \ingroup complex16OTHERauxiliary
  104: *
  105: *  =====================================================================
  106:       SUBROUTINE ZLAG2C( M, N, A, LDA, SA, LDSA, INFO )
  107: *
  108: *  -- LAPACK auxiliary routine --
  109: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  110: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
  111: *
  112: *     .. Scalar Arguments ..
  113:       INTEGER            INFO, LDA, LDSA, M, N
  114: *     ..
  115: *     .. Array Arguments ..
  116:       COMPLEX            SA( LDSA, * )
  117:       COMPLEX*16         A( LDA, * )
  118: *     ..
  119: *
  120: *  =====================================================================
  121: *
  122: *     .. Local Scalars ..
  123:       INTEGER            I, J
  124:       DOUBLE PRECISION   RMAX
  125: *     ..
  126: *     .. Intrinsic Functions ..
  127:       INTRINSIC          DBLE, DIMAG, CMPLX
  128: *     ..
  129: *     .. External Functions ..
  130:       REAL               SLAMCH
  131:       EXTERNAL           SLAMCH
  132: *     ..
  133: *     .. Executable Statements ..
  134: *
  135:       RMAX = SLAMCH( 'O' )
  136:       DO 20 J = 1, N
  137:          DO 10 I = 1, M
  138:             IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
  139:      $          ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
  140:      $          ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
  141:      $          ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
  142:                INFO = 1
  143:                GO TO 30
  144:             END IF
  145:             SA( I, J ) = CMPLX( A( I, J ) )
  146:    10    CONTINUE
  147:    20 CONTINUE
  148:       INFO = 0
  149:    30 CONTINUE
  150:       RETURN
  151: *
  152: *     End of ZLAG2C
  153: *
  154:       END