[Numpy-discussion] min() of array containing NaN

Ryan May rmay31@gmail....
Fri Aug 15 17:04:49 CDT 2008


>
> Availability of the NaN functionality in a method of ndarray
>
> The last point is key.  The NaN behavior is central to analyzing real
> data containing unavoidable bad values, which is the bread and butter
> of a substantial fraction of the user base.  In the languages they're
> switching from, handling NaNs is just part of doing business, and is
> an option of every relevant routine; there's no need for redundant
> sets of routines.  In contrast, numpy appears to consider data
> analysis to be secondary, somehow, to pure math, and takes the NaN
> functionality out of routines like min() and std().  This means it's
> not possible to use many ndarray methods.  If we're ready to handle a
> NaN by returning it, why not enable the more useful behavior of
> ignoring it, at user discretion?
>

Maybe I missed this somewhere, but this seems like a better use for masked
arrays, not NaN's.  Masked arrays were specifically designed to add
functions that work well with masked/invalid data points.  Why reinvent the
wheel here?

Ryan

-- 
Ryan May
Graduate Research Assistant
School of Meteorology
University of Oklahoma
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://projects.scipy.org/pipermail/numpy-discussion/attachments/20080815/13e9494e/attachment-0001.html 


More information about the Numpy-discussion mailing list