Python

Manipulating dictionaries

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Join Date: Oct 2008

Posts: 13

Reputation: Devlan is an unknown quantity at this point

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Devlan

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Manipulating dictionaries

Oct 20th, 2008

Here I go with yet another of my don't-get-the-syntax-problems. For some reason I tend to get a lot more from putting a question here than reading through a few dozen pages of documentation, which I have once again done.

Say I have a dictionary as a basic data structure in a program. I'd like to be able - as a user input - to add additional keys to existing values and additonal values to existing keys. Everything I read feels like it comes almost to the point of explaining it and then says something like "And that's all of it".
Any hints would be great!

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Join Date: Jul 2008

Posts: 1,067

Reputation: jlm699 is a jewel in the rough

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jlm699

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Knows where his Towel is

Re: Manipulating dictionaries

Oct 20th, 2008

You can't necessarily "add additional keys to existing values", unless you simply meant add additional key/value pairs to the existing dictionary. Here's some examples of adding elements to a dictionary:

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>>> d = {'a':1, 'b':2, 'c':3}
>>> d['d'] = 4
>>> d['a'] = [ d['a'], 12, 13 ]
>>> d['e'] = []
>>> d['e'].append('foobar')
>>> d
{'a': [1, 12, 13], 'c': 3, 'b': 2, 'e': ['foobar'], 'd': 4}
>>>
>>> d = {'a':1, 'b':2, 'c':3}
>>> d['d'] = 4
>>> d['a'] = [ d['a'], 12, 13 ]
>>> d['e'] = []
>>> d['e'].append('foobar')
>>> d
{'a': [1, 12, 13], 'c': 3, 'b': 2, 'e': ['foobar'], 'd': 4}
>>>