comparing lists

[Paul Magwene]

On Wed, 08 May 2002 18:40:26 -0400, Mark McEahern wrote:

> Suppose I want to do a boolean comparison (equal or not equal) of two
> lists case-insensitively and I don't care about order.  I can do this:
> 
> 1.  Create temporary copies that are lowercased and use the in operator:
> 
> 2.  Sort temporary copies, then then compare them.
> 
> Are there other options?  Is there a strong reason to prefer one
> approach over the other?
> 
> Sample code below.
> 
> Thanks,
> 
> // mark
> 
> 

If you know you're dealing with lists of strings why don't you use the
"join" methods in the string module.

For example:

>>> import string
>>> l = ['a','b','c']
>>> m = ['C','b','a']
>>> n = ['A','B','c']
>>> lstr = string.join(l)
>>> mstr = string.join(m)
>>> nstr = string.join(n)
>>> lstr.lower()
'a b c'
>>> lstr.lower() == nstr.lower()
1
>>> lstr.lower() == mstr.lower()
0
>>>

--Paul