Hi, Trying out the example from from http://www.scilab.org/doc/intro/node25.html -->deff('[x]=foo(y)','if y>0 then, x=1; else, x=-1; end') -->x=-1:0.1:1 -->plot(x,foo(x)) I would expect the graph of a step function jumping from -1 to 1 at 0. Instead I get a constant function y == -1 for -1 <= x <= 1. What's going wrong? Klaus