Definite integration using the trapezium rule

trapezium.py

from __future__ import division

def trapezium(f, n, a, b):
	''' 
        f- function [f(x)]
        n- number of trapeziums
        a- lower limit
        b- upper limit
        Returns definite integral of f(x) from range a to b
	'''
	h = (b-a)/n	
	area = 0.5*h
	sum_y = f(a)+f(b)
	
	part_sum = 0

	for i in xrange(1, n):
		part_sum += f(a+h*i)

	sum_y += 2*part_sum
	area *= sum_y	
	return area

def f(x):
	return x ** 2

print trapezium(f, 100000, 0, 3)