# ?sum1

Forms the 1-norm of the complex vector using the true absolute value.

## Syntax

res = scsum1( n, cx, incx )

res = dzsum1( n, cx, incx )

## Description

Given a complex vector cx, scsum1/dzsum1 functions take the sum of the absolute values of vector elements and return a single/DOUBLE PRECISION result, respectively. These functions are based on scasum/dzasum from Level 1 BLAS, but use the true absolute value and were designed for use with clacon/zlacon.

## Input Parameters

n

  INTEGER. Specifies the number of elements in the vector cx.

cx

  COMPLEX for scsum1

  COMPLEX*16 for dzsum1

  Array, DIMENSION at least `(1+(n-1)*abs(incx))`.

  Contains the input vector whose elements will be summed.

incx

  INTEGER. Specifies the spacing between successive elements of cx (incx > 0).

## Output Parameters

res

  REAL for scsum1

  DOUBLE PRECISION for dzsum1

  Contains the sum of absolute values.

Parent topic: Auxiliary Routines