[Numpy-discussion] ndarray methods vs numpy module functions

Sebastian Haase haase@msg.ucsf....
Mon Jun 23 18:10:26 CDT 2008

On Mon, Jun 23, 2008 at 10:31 AM, Bob Dowling <rjd4@cam.ac.uk> wrote:
> [ I'm new here and this has the feel of an FAQ but I couldn't find
> anything at http://www.scipy.org/FAQ .  If I should have looked
> somewhere else a URL would be gratefully received. ]
> What's the reasoning behind functions like sum() and cumsum() being
> provided both as module functions (numpy.sum(data, axis=1)) and as
> object methods (data.sum(axis=1)) but other functions - and I stumbled
> over diff() - only being provided as module functions?
Hi Bob,
this is a very good question.
I think the answers are
a) historical reasons AND, more importantly, differing personal preferences
b) I would file  the missing data.diff() as a bug.  There are many
inconsistencies left in such a big project like numpy.  And filing
bugs might be the best way of keeping track of them and getting them
fixes eventually...
(( a much more dangerous example is numpy.resize and data.resize,
which do (slightly) different things !!))

Others, please correct my .....

Welcome on the list.

Sebastian Haase

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