SuperLU: SRC/dzsum1.c File Reference

# SRC/dzsum1.c File Reference

Takes sum of the absolute values of a complex vector and returns a double precision result. More...

`#include "slu_dcomplex.h"`
`#include "slu_Cnames.h"`

## Defines
#define | CX(I) cx[(I)-1]
## Functions
double | dzsum1_ (int *n, doublecomplex *cx, int *incx)

## Detailed Description

         -- LAPACK auxiliary routine (version 2.0) --
         Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
         Courant Institute, Argonne National Lab, and Rice University
         October 31, 1992

## Define Documentation

#define CX | ( | I |  | ) | cx[(I)-1]

## Function Documentation

double dzsum1_ | ( | int * | n,
|  | doublecomplex * | cx,
|  | int * | incx |
| ) |  |  |

        Purpose
        =======

        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.

        Contributed by Nick Higham for use with ZLACON.

        Arguments
        =========

        N       (input) INT
                The number of elements in the vector CX.

        CX      (input) COMPLEX*16 array, dimension (N)
                The vector whose elements will be summed.

        INCX    (input) INT
                The spacing between successive values of CX.  INCX > 0.

        =====================================================================