Finding matching keys in two large dictionaries and doing it fast

Question

I am trying to find corresponding keys in two different dictionaries. Each has about 600k entries.

Say for example:

    myRDP = { \'Actinobacter\':          


        

Answer 1

You could start by finding the common keys and then iterating over them. Set operations should be fast because they are implemented in C, at least in modern versions of Python.

common_keys = set(myRDP).intersection(myNames)
for key in common_keys:
    print key, myNames[key]