Subsetting a dictionary

[Will Newton]

Aahz Maruch wrote:

>>On average this makes the code ~10x slower. I haven't done an in depth
>>analysis of how the routine is called, but my "backwards" way of doing
>>things seems much faster for my task.
> 
> While it's possible you're right, my gut instinct is that Emile's way
> will be faster unless your subset almost always includes most of the
> dictionary.

I ran the profiles, trust me, my way is faster, just not fast enough. :)