Exponential moving average generator example in Python

ema_gen.py

def consumer(func):
	'''
	Decorator taking care of initial next() call to "sending" generators

	From PEP-342
	http://www.python.org/dev/peps/pep-0342/
	'''
	def wrapper(*args,**kw):
		gen = func(*args, **kw)
		next(gen)
		return gen
	wrapper.__name__ = func.__name__
	wrapper.__dict__ = func.__dict__
	wrapper.__doc__  = func.__doc__
	return wrapper

@consumer
def ema(alpha=0.5):
	'''
	Exponential moving average generator

	http://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average

	Higher alpha discounts old results faster, alpha in range (0, 1).
	'''
	current, average = 0, 0
	while True:
		average = current * alpha + average * (1 - alpha)
		current = yield average

if __name__ == '__main__':
	# example
	g = ema()
	while True:
		print g.send(10)
		raw_input("Hit Enter to continue...")