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| Newsgroups | comp.lang.python |
| Date | Sat, 9 Mar 2013 12:30:11 -0800 (PST) |
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| Subject | Re: itertools.filterfalse - what is it good for |
| From | Miki Tebeka <miki.tebeka@gmail.com> |
| Cc | python-list@python.org |
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> can anybody point out a situation where you really need itertools.filterfalse() ?
Sometimes you get the predicate as a parameter to another function. This way if you want to filter out things you can easily do it. Other language (such as Clojure) have a "complement" function that removes the need of filterfalse.
For example (Python 3):
def percent_spam(is_spam, documents):
n_spam = sum(1 for _ in filter(is_spam, documents))
n_ham = sum(1 for _ in filterfalse(is_spam, documents))
return float(n_spam) / (n_ham + n_spam)
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itertools.filterfalse - what is it good for Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2013-03-08 16:45 +0000 Re: itertools.filterfalse - what is it good for Neil Cerutti <neilc@norwich.edu> - 2013-03-08 17:02 +0000 Re: itertools.filterfalse - what is it good for Miki Tebeka <miki.tebeka@gmail.com> - 2013-03-09 12:30 -0800 Re: itertools.filterfalse - what is it good for Miki Tebeka <miki.tebeka@gmail.com> - 2013-03-09 12:30 -0800
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