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Première mise à jour de lapack et blas.

    1: *> \brief \b DZSUM1 forms the 1-norm of the complex vector using the true absolute value.
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at
    6: *            http://www.netlib.org/lapack/explore-html/
    7: *
    8: *> \htmlonly
    9: *> Download DZSUM1 + dependencies
   10: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dzsum1.f">
   11: *> [TGZ]</a>
   12: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dzsum1.f">
   13: *> [ZIP]</a>
   14: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dzsum1.f">
   15: *> [TXT]</a>
   16: *> \endhtmlonly
   17: *
   18: *  Definition:
   19: *  ===========
   20: *
   21: *       DOUBLE PRECISION FUNCTION DZSUM1( N, CX, INCX )
   22: *
   23: *       .. Scalar Arguments ..
   24: *       INTEGER            INCX, N
   25: *       ..
   26: *       .. Array Arguments ..
   27: *       COMPLEX*16         CX( * )
   28: *       ..
   29: *
   30: *
   31: *> \par Purpose:
   32: *  =============
   33: *>
   34: *> \verbatim
   35: *>
   36: *> DZSUM1 takes the sum of the absolute values of a complex
   37: *> vector and returns a double precision result.
   38: *>
   39: *> Based on DZASUM from the Level 1 BLAS.
   40: *> The change is to use the 'genuine' absolute value.
   41: *> \endverbatim
   42: *
   43: *  Arguments:
   44: *  ==========
   45: *
   46: *> \param[in] N
   47: *> \verbatim
   48: *>          N is INTEGER
   49: *>          The number of elements in the vector CX.
   50: *> \endverbatim
   51: *>
   52: *> \param[in] CX
   53: *> \verbatim
   54: *>          CX is COMPLEX*16 array, dimension (N)
   55: *>          The vector whose elements will be summed.
   56: *> \endverbatim
   57: *>
   58: *> \param[in] INCX
   59: *> \verbatim
   60: *>          INCX is INTEGER
   61: *>          The spacing between successive values of CX.  INCX > 0.
   62: *> \endverbatim
   63: *
   64: *  Authors:
   65: *  ========
   66: *
   67: *> \author Univ. of Tennessee
   68: *> \author Univ. of California Berkeley
   69: *> \author Univ. of Colorado Denver
   70: *> \author NAG Ltd.
   71: *
   72: *> \ingroup complex16OTHERauxiliary
   73: *
   74: *> \par Contributors:
   75: *  ==================
   76: *>
   77: *> Nick Higham for use with ZLACON.
   78: *
   79: *  =====================================================================
   80:       DOUBLE PRECISION FUNCTION DZSUM1( N, CX, INCX )
   81: *
   82: *  -- LAPACK auxiliary routine --
   83: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
   84: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   85: *
   86: *     .. Scalar Arguments ..
   87:       INTEGER            INCX, N
   88: *     ..
   89: *     .. Array Arguments ..
   90:       COMPLEX*16         CX( * )
   91: *     ..
   92: *
   93: *  =====================================================================
   94: *
   95: *     .. Local Scalars ..
   96:       INTEGER            I, NINCX
   97:       DOUBLE PRECISION   STEMP
   98: *     ..
   99: *     .. Intrinsic Functions ..
  100:       INTRINSIC          ABS
  101: *     ..
  102: *     .. Executable Statements ..
  103: *
  104:       DZSUM1 = 0.0D0
  105:       STEMP = 0.0D0
  106:       IF( N.LE.0 )
  107:      $   RETURN
  108:       IF( INCX.EQ.1 )
  109:      $   GO TO 20
  110: *
  111: *     CODE FOR INCREMENT NOT EQUAL TO 1
  112: *
  113:       NINCX = N*INCX
  114:       DO 10 I = 1, NINCX, INCX
  115: *
  116: *        NEXT LINE MODIFIED.
  117: *
  118:          STEMP = STEMP + ABS( CX( I ) )
  119:    10 CONTINUE
  120:       DZSUM1 = STEMP
  121:       RETURN
  122: *
  123: *     CODE FOR INCREMENT EQUAL TO 1
  124: *
  125:    20 CONTINUE
  126:       DO 30 I = 1, N
  127: *
  128: *        NEXT LINE MODIFIED.
  129: *
  130:          STEMP = STEMP + ABS( CX( I ) )
  131:    30 CONTINUE
  132:       DZSUM1 = STEMP
  133:       RETURN
  134: *
  135: *     End of DZSUM1
  136: *
  137:       END