### reduceDicts.py ###
from operator import add
def reduceDicts(binOp, dicts):
reduced = {}
for dict in dicts:
for k,v in dict.iteritems():
try:
reduced[k] = binOp(reduced[k], v)
except KeyError:
reduced[k] = v
return reduced
def addDicts(*dicts):
return reduceDicts(add, dicts)
######################################################
# test in the interpreter
>>> from reduceDicts import reduceDicts,addDicts
>>> d1 = {"a":2, "b":3, "c":-2}
>>> d2 = {"a":-3, "c":12, "d":4, "f":1}
>>> addDicts(d1,d2)
{'a': -1, 'c': 10, 'b': 3, 'd': 4, 'f': 1}
>>> reduceDicts(max, [d1,d2])
{'a': 2, 'c': 12, 'b': 3, 'd': 4, 'f': 1}
