In Python, how do I find the index of an sub-item given a list?

Question

Given the list:

li = ['a', 'b', 'new', 'mpilgrim', 'z', 'example', 'new', 'two', 'elements']

How do I find the (first) index containing the string amp? Note that amp is contained the word example.

FYI, this works: li.index("example")

But this does not: li.index("amp")

related: [Python: find first element in a sequence that matches a predicate](http://stackoverflow.com/q/8534256/4279) — jfs, Aug 14 '13 at 09:19

score 10 · Accepted Answer · edited Aug 14 '13 at 09:14

10

You can use a generator expression with next and enumerate:

>>> next((i for i,x in enumerate(li) if 'amp' in x), None)
5

This will return None if no such item was found.

edited Aug 14 '13 at 09:14

TerryA

answered Aug 14 '13 at 09:02

Ashwini Chaudhary

1 Answers1