Hi, The following example copied from the pro builder guide. (Page 23) but When I copy it into the software I get an error message. Can you check me why , please ? line = 0 Increase = (Close – Close[1]) > 0 i = 0 WHILE Increase[i] DO i = i + 1 // Si high – low, we exit the loop to avoid a division by zero. IF (high-low) = 0 then BREAK ENDIF osc = (close – low) / (high – low) line = AVERAGE [i] (osc) WEND RETURN line