function y=logi(x,lambda)
  y=lambda*x.*(1-x)
endfunction
scf(1);
x=(0.:0.01:1)';
A=.8;
y1=logi(x,A);
y2=logi(y1,A);
plot2d(x,[x y1 y2],[1 2 3]);
legend('x','logi','logi^2');
halt();
xdel(1);