zgsgiv.m

similer program for matlab

## Copyright (C) 1996, 1998, 2000, 2005, 2007
##               Auburn University.  All rights reserved.
##
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## -*- texinfo -*-
## @deftypefn {Function File} {[a, b] =} zgsgiv (@var{c}, @var{s}, @var{a}, @var{b})
## Apply givens rotation c,s to row vectors @var{a}, @var{b}.
## No longer used in zero-balancing (__zgpbal__); kept for backward
## compatibility.
## @end deftypefn

## Author: A. S. Hodel <[e-mail]>
## Created: July 29, 1992
## Convertion to Octave by R. Bruce Tenison July 3, 1994

function [a, b] = zgsgiv (c, s, a, b)

  if (nargin != 4)
    print_usage ();
  endif

  t1 = c*a + s*b;
  t2 = -s*a + c*b;
  a = t1;
  b = t2;

endfunction