[Numpy-discussion] Re: numpy, overflow, inf, ieee, and rich comparison

Alex Martelli aleaxit at yahoo.com
Tue Oct 24 06:34:37 EDT 2000


"Charles Boncelet" <boncelet at udel.edu> wrote in message
news:39F4A4DE.9202540A at udel.edu...
    [snip]
> > > >  Guido thinks that 2/3 returning 0 was a design mistake,
    [snip]
> I often want 2/3 to equal 0, but then again I learned FORTRAN years ago.
>
> My point is that if 2/3 = 0.667, then special syntax is needed for those
> applications that want 2/3=0.  The current syntax is very simple, even
> if slightly confusing to a complete newby.

Note that a prominent beginners' language, Pascal, avoids this
specific design mistake: 2/3 is 0.6666667, and you use 2 div 3
if you want truncating-division.  2/3 returns a floating-point
number also in another language that may well be the only one
a beginner knows, Visual Basic in all of its forms.  Therefore,
it is quite possible that people who have programmed before get
very surprised by the truncation -- not everybody is learning
Fortran, C or Java as their first language...:-).

I'd rather have 2/3 return a _rational_ number 2/3, as in
Scheme -- another reasonably popular beginners' language.
But that requires having rationals built-in, I guess...:-).


Alex






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