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I'm trying to find a match value from a keyword using python. My values are stored in a list (my_list) and in the below example I'm trying to find the word 'Webcam'. I only want to return the word if it is fully matched.

Using item.find works but only if the case matches (i.e. upper and lower case must be correct). But I want to return the item regardless of the case, However, I do not wish to match all instances of the string like 'Webcamnew' so using the any() method won't work I think. Does anyone know how to do this..?

my_list = ['webcam', 'home', 'Space', 'Maybe later', 'Webcamnew'] for item in my_list: if item.find("Webcam") != -1: print item
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    Convert every string you are comparing to lowercase with string.lower() Commented Jun 19, 2014 at 18:05
  • if there is a way to do it without converting to lower/uppercase that would be useful. Commented Jun 19, 2014 at 18:07

2 Answers 2

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my_list = ['webcam', 'home', 'Space', 'Maybe later', 'Webcamnew'] for item in my_list: if 'webcam' == item.lower() print item.lower()

Note: Strings are immutable in Python - it doesn't modify the string in the list.

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if there is a way to do it without converting to lower/uppercase that would be useful as when you convert back you loose the correct case.
Strings are immutable
What do you mean "convert back"? The code shown preserves item?
This is the correct answer. @john "TESTING".lower() does not change the case of the original "TESTING" string. This is impossible, as strings are immutable in Python (they cannot be changed). It creates a NEW string, with all lowercase letters, and compares that instead.
Thanks, I see what it does now.
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If for some reason you REALLY need to compare case insensitive strings (rather than generating a same-case string) you can use regular expressions with the re.IGNORECASE flag. This is a terrible idea for what you seem to be trying to do, but the code is:

import re my_list = ['webcam', 'home', 'Space', 'Maybe later', 'Webcamnew'] for item in my_list: if re.match("webcam$",item, flags=re.I): # re.I == re.IGNORECASE print item

The reason this is a Bad Idea is that using regular expressions for simple matching is kind of like using a backhoe to dig post holes. Sure, you can do it, but it's expensive, time-consuming, and has the opportunity to introduce errors you didn't think about until you accidentally swung the boom through your living room window.

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If you want to do this, you will need to use re.escape() and append a $.
+1 for alternative route w/ warning
@GregHewgill why would you need to do re.escape()? You're right about $ though, adding that now.
@AdamSmith: Well you wouldn't need it for a literal "webcam", but you would need it if you're searching for something taken from user input, for example. A string like "foo[bar" is an invalid regex.
@GregHewgill understood. I don't know if that's part of what the OP needs though, as his example is matching against a literal string. If so it'd be easier to do re.match("\b"+re.escape(raw_input())+"\b", " ".join(my_list), re.I)

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