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Re: int2interval, frac2interval, rat2interval

On Apr 20 2012, Vincent Lefevre wrote:


Er, no.  Firstly, in mathematics, 1/0 is undefined in the integers,
reals, rationals and complex numbers.  It can be added to any of them,
but only at the cost of breaking some of their important properties.


It can be added, but AFAIK, there are well-known no conventions
about it (contrary to Rbar).


Eh?  The usual completion of the real line by adding infinities leaves
1/0 as undefined.  While there are conventions that define extend the
reals to include 1/0, none are widely used, unlike the usual extension.
IEEE 754 is mathematically inconsistent, in treating a single value
both as true zero and a positive infinitesimal, and that leads to no
end of trouble.

Regards,
Nick Maclaren.