%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
N=100; tol=2^(-53);
A =randn(N); 

E0=expm(A);
E1=expm_1(A,tol);
E2=expm_1diagpad(A,tol);
% Maximum error
norm(A,1)
HE=max(max(abs(E0-E1)))
HE1=max(max(abs(E0-E2)))