begin
	comment function ln;
	real x, y;
	integer n;
	
	% for x:= 0 step 0.1 until 3.0 do %
	for n:= 0 step 1 until 30 do
	begin
		if n = 0 then x := epsilon else x := n * 0.1;
		y := ln (x);
		write( x); writeon( y); 
	end 

end
----stdout
Algol60 program changes:
- input/output functions
- no real control variable in for-loop