GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages


Manual Reference Pages  -  HPL_DLANGE (3)

NAME

HPL_dlange - Compute ||A||.

CONTENTS

Synopsis
Description
Arguments
Example
See Also

SYNOPSIS

#include "hpl.h"

double HPL_dlange( const HPL_T_NORM NORM, const int M, const int N, const double * A, const int LDA );

DESCRIPTION

HPL_dlange returns the value of the one norm, or the infinity norm, or the element of largest absolute value of a matrix A:

max(abs(A(i,j))) when NORM = HPL_NORM_A,
norm1(A), when NORM = HPL_NORM_1,
normI(A), when NORM = HPL_NORM_I,

where norm1 denotes the one norm of a matrix (maximum column sum) and normI denotes the infinity norm of a matrix (maximum row sum). Note that max(abs(A(i,j))) is not a matrix norm.

ARGUMENTS

NORM (local input) const HPL_T_NORM
  On entry, NORM specifies the value to be returned by this function as described above.
M (local input) const int
  On entry, M specifies the number of rows of the matrix A. M must be at least zero.
N (local input) const int
  On entry, N specifies the number of columns of the matrix A. N must be at least zero.
A (local input) const double *
  On entry, A points to an array of dimension (LDA,N), that contains the matrix A.
LDA (local input) const int
  On entry, LDA specifies the leading dimension of the array A. LDA must be at least max(1,M).

EXAMPLE

#include "hpl.h"

int main(int argc, char *argv[])
{
double a[2*2];
a[0] = 1.0; a[1] = 3.0; a[2] = 2.0; a[3] = 4.0;
norm = HPL_dlange( HPL_NORM_I, 2, 2, a, 2 );
printf("norm=%f\n", norm);
exit(0); return(0);
}

SEE ALSO

HPL_dlaprnt (3), HPL_fprintf (3).
Search for    or go to Top of page |  Section 3 |  Main Index


HPL 2.1 HPL_DLANGE (3) October 26, 2012

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.