Mercurial > matrix-functions
view mftoolbox/logm_cond.m @ 0:8f23314345f4 draft
Create local repository for matrix toolboxes. Step #0 done.
author | Antonio Pino Robles <data.script93@gmail.com> |
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date | Wed, 06 May 2015 14:56:53 +0200 |
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function c = logm_cond(A) %LOGM_COND Relative condition number of matrix logarithm. % LOGM_COND(A) is the relative condition number in the Frobenius % norm of the matrix logarithm at the matrix A. n = length(A); N = n^2; K = zeros(N); E = zeros(n); if ~isequal(A,triu(A)) A = schur(A,'complex'); end for j = 1:N e = zeros(N,1); e(j) = 1; E(:) = e; X = logm_frechet_pade(A,E); K(:,j) = X(:); end c = norm(K) * norm(A,'fro') / norm(logm(A),'fro');