Thanks, Chris. That's the algorithm I was looking for. And I will be converting most of this data to objects. Thanks again.
-----Original Message----- From: Chris Rebert [mailto:c...@rebertia.com] Sent: Wednesday, February 29, 2012 11:44 PM Subject: Re: Help needed: dynamically pull data from different levels of a dict On Wed, Feb 29, 2012 at 7:56 PM, Peter Rubenstein <peter.rubenst...@hotmail.com> wrote: > Hi, > > I'd appreciate a bit of help on this problem. I have some data that > I've converted to a dict and I want to pull out individual pieces of it. > > Simplified version-- > > a={'1':'a', '2':'b', '3':{4:'d'}, '5':{'6': {'7': [ {'8':'e'}, > {'9':'f'} ] } } } > > I'd like to be able to code something like: > > data_needed = ['1', '2', '3:4', '5:6:7-8'] for val in data_needed: > answer=extract_from(a,val) > print answer > > And get: > a > b > c "c" apparently sprung completely out of thin air... > d > e > > Problem is I can't figure out what extract_from would look like, such > that it would proceed dynamically down to the right level. I'm open > to the possibility that I'm not approaching this the right way. data_needed = ['1', '2', ('3', '4'), ('5', '6', '7', 0, '8')] def extract_from(mapping, key_path): current = mapping for key in key_path: current = current[key] return current I would perhaps try and restructure the data into something less generic than nested dicts & lists, e.g. objects. You then might be able to introduce helper querying methods. I would also be worried about Law of Demeter violations, but fortunately your concrete example doesn't reach any deeper than 2 levels. Cheers, Chris -- http://chrisrebert.com -- http://mail.python.org/mailman/listinfo/python-list
