my_rank.m

MATLAB算法实现

function r = my_rank(A,tol)
%RANK   Matrix rank.
%   RANK(A) provides an estimate of the number of linearly
%   independent rows or columns of a matrix A.
%   RANK(A,tol) is the number of singular values of A
%   that are larger than tol.
%   RANK(A) uses the default tol = max(size(A)) * norm(A) * eps.

%   Copyright 1984-2002 The MathWorks, Inc. 
%   $Revision: 5.11 $  $Date: 2002/04/08 23:51:52 $

s = svd(A);
if nargin==1
   tol = max(size(A)') * max(s) * eps;
end
r = sum(s > tol);