list subsetting

Jeff McNeil jeff at jmcneil.net
Wed Jan 21 23:09:19 CET 2009


On Jan 21, 4:53 pm, culpritNr1 <ig2ar-s... at yahoo.co.uk> wrote:
> Hello All,
>
> Say I have a list like this:
>
> a = [0 , 1, 3.14, 20, 8, 8, 3.14]
>
> Is there a simple python way to count the number of 3.14's in the list in
> one statement?
>
> In R I do like this
>
> a = c(0 , 1, 3.14, 20, 8, 8, 3.14)
>
> length( a[ a[]==3.14 ] )
>
> How do I do that in standard python?
>
> (Note that this is just an example, I do not mean to use == in floating
> point operations.)
>
> Thank you
>
> culpritNr1
>
> --
> View this message in context:http://www.nabble.com/list-subsetting-tp21593123p21593123.html
> Sent from the Python - python-list mailing list archive at Nabble.com.

Just the number of occurrences? Count method?

Python 2.6 (r26:66714, Oct 29 2008, 08:30:04)
[GCC 4.1.2 20070925 (Red Hat 4.1.2-33)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> [1,2,3,3.14,3.14,5,66].count(3.14)
2
>>>

Jeff



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