Hello.

Maybe, having the smallest standard set of a nulber could be a good thing.
Here are some examples.

   1. 1 is an integer.
   2. 1/2 is a rational.
   3. 2.3 and pi are reals.
   4. 2i and i are imaginary complexes.
   5. 4+5i is a complex.

Then something like "integer + complex" should be treated as a complex. By
giving an integer id for the kind of a number, and by choosing integer_id <
rational_id < reals_id < imaginary_id < complexe_id, then the kind of
number could be the maximum of all the id met in an expression.

What do you think about that ?

Christophe BAL


2014-03-04 12:36 GMT+01:00 Sergey Kirpichev <[email protected]>:

> On Tuesday, March 4, 2014 9:38:22 AM UTC+4, Chris Smith wrote:
>>
>> Something that seems a little counter-intuitive to me (having now worked
>> with the assumptions a bit) is the decision to let 2, I and 2 + I all be
>> considered complex
>>
>
> I'm little surprised, what could be counter-intuitive here from the
> mathematical point of view?
>
>
>> It seems like it would be more useful to consider them be onlny real,
>> imaginary and complex, resepectively.
>>
>
> Some shortcuts for internal use may be convenient, however.  E.g.
> Q.nonzero_imaginary or something.
>
> The way it is right now, the only way to say that something has a non-zero
>> real and imaginary part is to write it as a + I*b, e.g. ask(Q.real(I**(a +
>> I*b)), Q.real(a) & Q.real(b))
>>
>
> But this does not mean a+I*b has a non-zero re/im parts!
>
> Also, consider some arithmetic, e.g. complex + complex != complex with
> your definition.  By killing field properties - you complicate other
> things, I guess...
>
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