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

[Charles Boncelet]

Greg Ewing wrote:
> 
> As a serious programmer, what I want is a straightforward
> and efficient way to specify the operation I want performed.
> 
You have phrased it quite clearly.  I can't agree more.

> Truncating and non-truncating division are very different
> operations, used for very different purposes. Which one
> I want depends on the algorithm I'm implementing. Whenever
> I write a division in my code, I know which one I want.
> But the only way I can tell Python which one to use
> is indirectly, by manipulating the types of operands
> I feed to the / operator.

In my programs, I manage this issue by trying to never
mix integer and floating point arithmetic.  In C or Fortran,
one can declare a variable to hold an integer or a float.
Then a single division symbol (/) is sufficient.

This thread started with the observation that Guido thinks
that 2/3=0 was an incorrect design decision.  Let me propose
that 2/3=0 is a correct design decision.  The *incorrect* 
decision was to leave the behavior of A/2 undetermined
until the type of A is determined.

If we need a second division symbol, let me suggest "//",
i.e., 2//3 = 0.666...

> 
> To me, this is so obviously wrong that I can't understand
> how any serious programmer could think it was right.

Well, since you put it that way, I have no option but to
agree. :-)

	Charlie Boncelet


-- 
Charles Boncelet                              302-831-8008
Dept of Electrical and Computer Engineering   302-831-4316 (fax)
University of Delaware                        boncelet at eecis.udel.edu
http://www.eecis.udel.edu/~boncelet/