[Partition a set into a ordered set of disjoint subsets] #python

partition.py

#!/usr/bin/python3

"""
File: partition.py
Author: Matthew Cole 
Date: 6/7/16
"""

def partition(collection, partitions):
	"""
	Partition a collection into a list of len(partitions)+1 disjoint unsorted lists of elements,
	whose union is collection,defined as: [-inf,part0),...[part_m,part_m+1),...,[part_n-1,inf]. 
	Partitions itself must be an iterable, and collection must be orderable.
	"""
	from operator import ge, lt
	
	partitions = sorted(set(partitions))
	
	#Set up the buckets
	filters = [list(filter(lambda x: lt(x,partitions[0]),collection))]
	filters.extend([list(filter(lambda x: ge(x,partitions[i]) and lt(x,partitions[i+1]),collection)) for i in range(len(partitions)-1)])
	filters.append(list(filter(lambda x: ge(x,partitions[-1]),collection)))
	return(filters)
	

if __name__ == "__main__":
	print(partition([1,9,4,16,16.7,10,1,100,200,-40], [10,1,10,100]))