Home > freetb4matlab > special-matrix > lauchli.m

lauchli

PURPOSE ^

% Creates the matrix [ ones(1,@var{n}); @var{mu}*eye(@var{n}) ]

SYNOPSIS ^

function A = lauchli(n,mu)

DESCRIPTION ^

% -*- texinfo -*-
% @deftypefn {Function File} {@var{a}} = lauchli (@var{n})
% @deftypefnx {Function File} {@var{a}} = lauchli (@var{n},@var{mu})
% Creates the matrix [ ones(1,@var{n}); @var{mu}*eye(@var{n}) ]
% The value @var{mu} defaults to sqrt(eps).
% This is an ill-conditioned system for testing the
% accuracy of the QR routine.
%
% @example
% @group
%       A = lauchli(15);
%       [Q, R] = qr(A);
%       norm(Q*R - A)
%       norm(Q'*Q - eye(rows(Q)))
% @end group
% @end example
% @end deftypefn
% @seealso {ones,zeros,eye}

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:
Generated on Fri 22-May-2009 15:13:00 by m2html © 2003