[Haskell-beginners] Error with floats in implementation of Horner's method.

Hi all, I have implemented Horner's method for evaluating a polynomial as follows: -- the nth horner element, given a list of coefficients and a value at which it needs to be evaluated horner_element l x n | n == (length l)-1 = last l | otherwise = (l !! n) + (horner_element l x (n+1))*x -- compute a polynomial given as a list of coefficients at the value x using horner's method. horner l x = horner_element l x 0