LAPACK

NAME¶

sum1 - sum1: sum | x_i | (in LAPACK)

SYNOPSIS¶

Functions¶

double precision function dzsum1 (n, cx, incx)
DZSUM1 forms the 1-norm of the complex vector using the true absolute value. real function scsum1 (n, cx, incx)
SCSUM1 forms the 1-norm of the complex vector using the true absolute value.

Detailed Description¶

Function Documentation¶

double precision function dzsum1 (integer n, complex16, dimension( ) cx, integer incx)¶

DZSUM1 forms the 1-norm of the complex vector using the true absolute value.

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.

Parameters



          N is INTEGER


          The number of elements in the vector CX.



          CX is COMPLEX*16 array, dimension (N)


          The vector whose elements will be summed.

INCX



          INCX is INTEGER


          The spacing between successive values of CX.  INCX > 0.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Contributors:

Nick Higham for use with ZLACON.

real function scsum1 (integer n, complex, dimension( * ) cx, integer incx)¶

SCSUM1 forms the 1-norm of the complex vector using the true absolute value.