[Python-Dev] Fwd: summing a bunch of numbers (or "whatevers")
Prabhu Ramachandran
prabhu@aero.iitm.ernet.in
Sun, 20 Apr 2003 11:39:23 +0530
>>>>> "AM" == Alex Martelli <aleax@aleax.it> writes:
[summing a sequence]
AM> Now, I think the obvious approach would be to have a function
AM> sum, callable with any non-empty homogeneous sequence
AM> (sequence of items such that + can apply between them),
AM> returning the sequence's summation -- now THAT might help for
AM> simplicity, clarity AND power.
FWIW, Numeric provides a sum function that mostly does what you want:
>>> from Numeric import *
>>> sum(range(999))
498501
>>> sum(['a', 'b', 'c'])
'abc'
# this one produces a slightly surprising result
>>> sum(['aaa', 'b', 'c'])
array([abc , a , a ],'O')
# but is easily explained in the context of multi-dimensional arrays.
Anyway, my point is most Numeric users are already comfortable with
the idea of a sum function. However, as someone already said, if you
argue that sum is necessary, what about product (which again Numeric
provides along with a host of other useful functions)?
cheers,
prabhu