%% 1-Norm Condition Number
% Calculate the 1-norm condition number of a matrix.
%
% Create a 3-by-3 matrix.

A = [1 0 -2;
     3 4  6;
    -1 5  7];

%
% Calculate the 1-norm condition number of A. The value of the 1-norm condition number for an m-by-n matrix is
% \kappa_1 \left( A \right) = \vert \vert A \vert \vert_1 \, \, \, \vert \vert A^{-1} \vert \vert _1,
% where the 1-norm is the maximum absolute column sum of the matrix given by
% \vert \vert A \vert \vert_1 = \underset{1 \le j \le n} \textrm{max} \sum_{i=1} ^{m} \vert a_{ij} \vert .

C = cond(A,1)

% For this matrix the condition number is not too large, so the matrix is not particularly sensitive to the inverse calculation.
% Copyright 2012 The MathWorks, Inc.