[Numpy-discussion] Log Arrays

T J tjhnson@gmail....
Thu May 8 14:55:19 CDT 2008

On 5/8/08, Anne Archibald <peridot.faceted@gmail.com> wrote:
> Is "logarray" really the way to handle it, though? it seems like you
> could probably get away with providing a logsum ufunc that did the
> right thing. I mean, what operations does one want to do on logarrays?
> add -> logsum
> subtract -> ?
> multiply -> add
> mean -> logsum/N
> median -> median
> exponentiate to recover normal-space values -> exp
> str -> ?

That's about it, as far as my usage goes.  Additionally, I would also
benefit from:


In addition to the elementwise operations, it would be nice to have

   logsum along an axis
   logprod along an axis

Whether these are through additional ufuncs or through a subclass is
not so much of an issue for me---either would be a huge improvement to
the current situation.  One benefit of a subclass, IMO, is that it
maintains the feel of non-log arrays.  That is, when I want to
multiply to logarrays, I just do x*y, rather than x+y....but I can
understand arguments that this might not be desirable.

More information about the Numpy-discussion mailing list