Nonlinear algorithm for controlling dynamical systems, particularly where linear methods fail.
obs=logsim(pert)
% Copyright (c) 1998 The University of Texas at Austin
function obs=logsim(pert)
%Subroutine for use with the Matlab file logdemo.m
%Iterates f(x) = mu * (x + pert) * (1 - (x + pert))
%mu = 3.5 corresponds to a period four attractor in the logistic map
global cur mu;
if (length(cur)==0)
cur = .2;
mu = 3.5;
end
in = pert + cur;
cur = mu * in * (1 - in);
%We must ensure that the system remains bounded in [0,1]. Since
%the applied perturbations are small, this code is rarely used.
if cur > 1
cur
cur = cur - floor(cur);
elseif cur < 0
cur
cur = cur - floor(cur);
end
obs = cur;