[Tutor] soundfile picker & rating system

[kevin parks]

I am a little bit stuck ....

I want to play a bunch of soundfiles randomly, but i want to give each 
soundfile a rating (say 0-100) and have the likelihood that the file be 
chosen be tied to its rating so that the higher the rating the more 
likely a file is to be chosen.  Then i need some additional flags for 
repetition, and some other business. I am guessing a dictionary would 
be a great way to do this, with the key being the soundfile name and 
the values being my ratings and other flags & associated data.

#soundfile name : [rating, %chance it will repeat/loop]
sfiles = { ("sf001") : [85, 15],
      ("sf002") : [25, 75],
      ("sf003") : [95, 45],
      ("sf004") : [35, 95] }


But i am stuck on how to do a random chooser that works according to my 
idea of choosing according to rating system. It seems to me to be a bit 
different that just choosing a weighted choice like so:

def windex(lst):
	'''an attempt to make a random.choose() function that makes weighted 
choices
	
	accepts a list of tuples with the item and probability as a pair
	like: >>> x = [('one', 0.25), ('two', 0.25), ('three', 0.5)]
	>>> y=windex(x)'''
	n = random.uniform(0, 1)
	for item, weight in lst:
		if n < weight:
			break
		n = n - weight
	return item


And i am not sure i want to have to go through what will be hundreds of 
sound files and scale their ratings by hand so that they all add up to 
100%. I just want to have a long list that i can add too whenever i 
want, and assign it a grade/rating according to my whims!

cheers,

kevin