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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 convertion 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: *> \date September 2012
  104: *
  105: *> \ingroup complex16OTHERauxiliary
  106: *
  107: *  =====================================================================
  108:       SUBROUTINE ZLAG2C( M, N, A, LDA, SA, LDSA, INFO )
  109: *
  110: *  -- LAPACK auxiliary routine (version 3.4.2) --
  111: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  112: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
  113: *     September 2012
  114: *
  115: *     .. Scalar Arguments ..
  116:       INTEGER            INFO, LDA, LDSA, M, N
  117: *     ..
  118: *     .. Array Arguments ..
  119:       COMPLEX            SA( LDSA, * )
  120:       COMPLEX*16         A( LDA, * )
  121: *     ..
  122: *
  123: *  =====================================================================
  124: *
  125: *     .. Local Scalars ..
  126:       INTEGER            I, J
  127:       DOUBLE PRECISION   RMAX
  128: *     ..
  129: *     .. Intrinsic Functions ..
  130:       INTRINSIC          DBLE, DIMAG
  131: *     ..
  132: *     .. External Functions ..
  133:       REAL               SLAMCH
  134:       EXTERNAL           SLAMCH
  135: *     ..
  136: *     .. Executable Statements ..
  137: *
  138:       RMAX = SLAMCH( 'O' )
  139:       DO 20 J = 1, N
  140:          DO 10 I = 1, M
  141:             IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
  142:      $          ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
  143:      $          ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
  144:      $          ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
  145:                INFO = 1
  146:                GO TO 30
  147:             END IF
  148:             SA( I, J ) = A( I, J )
  149:    10    CONTINUE
  150:    20 CONTINUE
  151:       INFO = 0
  152:    30 CONTINUE
  153:       RETURN
  154: *
  155: *     End of ZLAG2C
  156: *
  157:       END