Some Scilab tips

Scilab has a unique feature which is potentially dangerous and can make debugging very difficult. This has to do with un-initialized variables. Let me give an example. In the code below, func1 calls func2 and func2 is supposed to return the average value of its input vector x.

function y = func1()

n = 10
x = linspace(0,1,n)
y = func2(x)

endfunction

function y = func2(x)

y = sum(x)/n
printf("n = %d\n", n)

endfunction

Note that in func2 I did not initialize the value of n but scilab will not complain. It checks if there is a variable of the same name in the calling function and if it finds it, then it uses the value of that variable. In my example, it will not be a problem since the correct value of n in func2 is the same as in func1. But you can imagine how disastrous this can be.