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asum(3) LAPACK asum(3)

NAME

asum - asum: sum | real( x_i ) | + | imag( x_i ) |

SYNOPSIS

Functions


double precision function dasum (n, dx, incx)
DASUM double precision function dzasum (n, zx, incx)
DZASUM real function sasum (n, sx, incx)
SASUM real function scasum (n, cx, incx)
SCASUM

Detailed Description

Function Documentation

double precision function dasum (integer n, double precision, dimension(*) dx, integer incx)

DASUM

Purpose:



    DASUM takes the sum of the absolute values.

Parameters

N 



          N is INTEGER


         number of elements in input vector(s)

DX



          DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) )

INCX



          INCX is INTEGER


         storage spacing between elements of DX

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Further Details:



     jack dongarra, linpack, 3/11/78.


     modified 3/93 to return if incx .le. 0.


     modified 12/3/93, array(1) declarations changed to array(*)

double precision function dzasum (integer n, complex*16, dimension(*) zx, integer incx)

DZASUM

Purpose:



    DZASUM takes the sum of the (|Re(.)| + |Im(.)|)'s of a complex vector and


    returns a double precision result.

Parameters

N 



          N is INTEGER


         number of elements in input vector(s)

ZX



          ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )

INCX



          INCX is INTEGER


         storage spacing between elements of ZX

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Further Details:



     jack dongarra, 3/11/78.


     modified 3/93 to return if incx .le. 0.


     modified 12/3/93, array(1) declarations changed to array(*)

real function sasum (integer n, real, dimension(*) sx, integer incx)

SASUM

Purpose:



    SASUM takes the sum of the absolute values.


    uses unrolled loops for increment equal to one.

Parameters

N 



          N is INTEGER


         number of elements in input vector(s)

SX



          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )

INCX



          INCX is INTEGER


         storage spacing between elements of SX

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Further Details:



     jack dongarra, linpack, 3/11/78.


     modified 3/93 to return if incx .le. 0.


     modified 12/3/93, array(1) declarations changed to array(*)

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

SCASUM

Purpose:



    SCASUM takes the sum of the (|Re(.)| + |Im(.)|)'s of a complex vector and


    returns a single precision result.

Parameters

N 



          N is INTEGER


         number of elements in input vector(s)

CX



          CX is COMPLEX array, dimension ( 1 + ( N - 1 )*abs( INCX ) )

INCX



          INCX is INTEGER


         storage spacing between elements of SX

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Further Details:



     jack dongarra, linpack, 3/11/78.


     modified 3/93 to return if incx .le. 0.


     modified 12/3/93, array(1) declarations changed to array(*)

Author

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