Gaussian Elimination Example (with partial pivoting): GEE, it's simple!: gee_its_simple_resid (A, x, b) - File Exchange

Code covered by the BSD License

Highlights from
Gaussian Elimination Example (with partial pivoting): GEE, it's simple!

gee_its_short (A, b) GEE_ITS_SHORT x=A\b, few comments, no error checking (just for line count)
gee_its_simple (A, b) GEE_ITS_SIMPLE solves A*x=b using a Gaussian Elimination Example (it's simple!)
gee_its_simple_backsolve (U, ... GEE_ITS_SIMPLE_BACKSOLVE x=U\b where U is upper triangular
gee_its_simple_factorize (A) GEE_ITS_SIMPLE_FACTORIZE Gaussian Elimination Example, with partial pivoting
gee_its_simple_forwardsolve (... GEE_ITS_SIMPLE_FORWARDSOLVE computes x=L\b where L is unit lower triangular
gee_its_simple_resid (A, x, b) GEE_ITS_SIMPLE_RESID compute the relative residual for x=A\b
gee_its_simple_test GEE_ITS_SIMPLE_TEST tests the "Gee! It's Simple!" package
gee_its_sweet (A, b) GEE_ITS_SWEET solves Ax=b with just x=A\b; it doesn't get sweeter than this
gee_its_too_short (A, b) GEE_ITS_TOO_SHORT x=A\b, no pivoting (thus unstable!), just bare bones
Contents.m
View all files

from Gaussian Elimination Example (with partial pivoting): GEE, it's simple! by Tim Davis
A set of simple functions that illustrate Gaussian Elimination with partial pivoting

gee_its_simple_resid (A, x, b)

function r = gee_its_simple_resid (A, x, b)
%GEE_ITS_SIMPLE_RESID compute the relative residual for x=A\b
% For non-singular matrices with reasonable condition number, the relative
% residual is typically O(eps).
%
% Example:
%
%   r = gee_its_simple_resid (A, x, b) ;
%
% See also: norm, gee_its_simple

% Copyright 2007, Timothy A. Davis.
% http://www.cise.ufl.edu/research/sparse

r = norm (A*x-b,inf) / (norm (A,inf) * norm (x, inf) + norm (b, inf)) ;

Highlights from Gaussian Elimination Example (with partial pivoting): GEE, it's simple!

Highlights from
Gaussian Elimination Example (with partial pivoting): GEE, it's simple!