Rob Williscroft wrote: > Steven D'Aprano wrote in news:4e1fd009$0$29986$c3e8da3 > $54964...@news.astraweb.com in gmane.comp.python.general: > >> I'm designing an API for some lightweight calculator-like statistics >> functions, such as mean, standard deviation, etc., and I want to support >> missing values. Missing values should be just ignored. E.g.: >> >> mean([1, 2, MISSING, 3]) => 6/3 = 2 rather than 6/4 or raising an error. > > If you can't make your mind up then maybe you shouldn't:
Heh, good point. It's not so much that I can't make up my mind -- I have a preferred solution in mind, but I want to hear what sort of interface for dealing with missing values others expect, and I don't want to prejudice others too greatly. > MISSING = MissingObject() > def mean( sequence, missing = MISSING ): So you think the right API is to allow the caller to specify what counts as a missing value at runtime? Are you aware of any other statistics packages that do that? -- Steven -- http://mail.python.org/mailman/listinfo/python-list