% Firefly Algorithm by X S Yang (Cambridge University)　　 %
% Usage: firefly_simple([number_of_fireflies,MaxGeneration])
%　eg:　 firefly_simple([12,50]);　　　　　　　　　　　　　%
% ======================================================== %
% This is a demo for 2D functions; for higher dimenions,　 %
% you should use fa_ndim.m or fa_mincon.m　　　　　　　　　%
% Parameters choice:
% Gamma should be linked with scales. Otherwise, the FA　　%
% the efficiency will be significantly reduced because　　 %
% the beta term may be too small.　　　　　　　　　　　　　%
% Similarly, alpha should also be linked with scales,　　　%
% the steps should not too large or too small, often　　　 %
% steps are about 1/10 to 1/100 of the domain size.　　　　%
% In addition, alpha should be reduced gradually　　　　　 %
% using alpha=alpha_0 delta^t during eteration t.　　　　　%
% Typically, delta=0.9 to 0.99 will be a good choice.