[Numpy-discussion] number ranges (was Re: Matlab page on scipy wiki)

[Bill B. <wb...@gm...>]

On 2/11/06, Gary Ruben <gr...@bi...> wrote:
>
> Sasha wrote:
> > On 2/10/06, Gary Ruben <gr...@bi...> wrote:
> >> ...  I must say that Travis's
> >> example numpy.r_[1,0,1:5,0,1] highlights my pet hate with python - tha=
t
> >> the upper limit on an integer range is non-inclusive.
> >
> > In this case you must hate that an integer range starts at 0 (I don't
> > think you would want len(range(10)) to be 11).


First, I think the range() function in python is ugly to begin with.  Why
can't python just support range notation directly like 'for a in 0:10'.  Or
with 0..10 or 0...10 syntax.  That seems to make a lot more sense to me tha=
n
having to call a named function.   Anyway, that's a python pet peeve, and
python's probably not going to change something so fundamental...

Second, sometimes zero-based, non-inclusive ranges are handy, and sometimes
one-based inclusive ranges are handy.  For array indexing, I personally lik=
e
zero based.  But sometimes I just want a list of N numbers like a human
would write it, from 1 to N, and in those cases it seems really odd for N+1
to show up.

This is a place where numpy could do something.  I think it would be nice i=
f
numpy had something like an 'irange' (inclusive range) function to
complement the 'arange' function.  They would act pretty much the same,
except irange(5) would return [1,2,3,4,5], and irange(1,5) would return
[1,2,3,4,5].

Anyway, I think I'm going to put a little irange function in my setup.

--Bill