Extracting specific elements of a list of lists in Python

Question

Here's a list:

foo=[(1, 2, {'weight': 1}), (1, 3, {'weight': 2}), (1, 4, {'weight': 3}), (`1 5, {'weight': 4}), (1, 6, {'weight': 5}), (1, 7, {'weight': 6})]

Say I wanted to extract a particular element of each list within foo and store it in a separate list.

e.g. I wanted to extract 2nd element from each list, within foo and save it in the array labelled bar.

bar=[2,3,4,5,6,7]

How can this be done in Python 2.7x?

vaultah · Accepted Answer · 2014-05-07 11:09:42Z

2

>>> from operator import itemgetter
>>> map(itemgetter(1), foo))
[2, 3, 4, 5, 6, 7]

answered May 7, 2014 at 11:09

vaultah

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Comments

sshashank124 · Accepted Answer · 2014-05-07 11:09:50Z

1

You can do that as:

bar = [i[1] for i in foo]
>>> print bar
[2,3,4,5,6,7]

answered May 7, 2014 at 11:09

sshashank124

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