How to split dictionary into multiple dictionaries fast

Question

I have found a solution but it is really slow:

def chunks(self,data, SIZE=10000):
    for i in xrange(0, len(data), SIZE):
        yield dict(data.items()[i:         


        

Answer 1

Since the dictionary is so big, it would be better to keep all the items involved to be just iterators and generators, like this

from itertools import islice

def chunks(data, SIZE=10000):
    it = iter(data)
    for i in xrange(0, len(data), SIZE):
        yield {k:data[k] for k in islice(it, SIZE)}

Sample run:

for item in chunks({i:i for i in xrange(10)}, 3):
    print item

Output

{0: 0, 1: 1, 2: 2}
{3: 3, 4: 4, 5: 5}
{8: 8, 6: 6, 7: 7}
{9: 9}