*> \brief \b DZSUM1 forms the 1-norm of the complex vector using the true absolute value.
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
*> \htmlonly
*> Download DZSUM1 + dependencies
*>
*> [TGZ]
*>
*> [ZIP]
*>
*> [TXT]
*> \endhtmlonly
*
* Definition:
* ===========
*
* DOUBLE PRECISION FUNCTION DZSUM1( N, CX, INCX )
*
* .. Scalar Arguments ..
* INTEGER INCX, N
* ..
* .. Array Arguments ..
* COMPLEX*16 CX( * )
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> DZSUM1 takes the sum of the absolute values of a complex
*> vector and returns a double precision result.
*>
*> Based on DZASUM from the Level 1 BLAS.
*> The change is to use the 'genuine' absolute value.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] N
*> \verbatim
*> N is INTEGER
*> The number of elements in the vector CX.
*> \endverbatim
*>
*> \param[in] CX
*> \verbatim
*> CX is COMPLEX*16 array, dimension (N)
*> The vector whose elements will be summed.
*> \endverbatim
*>
*> \param[in] INCX
*> \verbatim
*> INCX is INTEGER
*> The spacing between successive values of CX. INCX > 0.
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date September 2012
*
*> \ingroup complex16OTHERauxiliary
*
*> \par Contributors:
* ==================
*>
*> Nick Higham for use with ZLACON.
*
* =====================================================================
DOUBLE PRECISION FUNCTION DZSUM1( N, CX, INCX )
*
* -- LAPACK auxiliary routine (version 3.4.2) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* September 2012
*
* .. Scalar Arguments ..
INTEGER INCX, N
* ..
* .. Array Arguments ..
COMPLEX*16 CX( * )
* ..
*
* =====================================================================
*
* .. Local Scalars ..
INTEGER I, NINCX
DOUBLE PRECISION STEMP
* ..
* .. Intrinsic Functions ..
INTRINSIC ABS
* ..
* .. Executable Statements ..
*
DZSUM1 = 0.0D0
STEMP = 0.0D0
IF( N.LE.0 )
$ RETURN
IF( INCX.EQ.1 )
$ GO TO 20
*
* CODE FOR INCREMENT NOT EQUAL TO 1
*
NINCX = N*INCX
DO 10 I = 1, NINCX, INCX
*
* NEXT LINE MODIFIED.
*
STEMP = STEMP + ABS( CX( I ) )
10 CONTINUE
DZSUM1 = STEMP
RETURN
*
* CODE FOR INCREMENT EQUAL TO 1
*
20 CONTINUE
DO 30 I = 1, N
*
* NEXT LINE MODIFIED.
*
STEMP = STEMP + ABS( CX( I ) )
30 CONTINUE
DZSUM1 = STEMP
RETURN
*
* End of DZSUM1
*
END