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Re: Rational[a,b] vs Rational[1,2]

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  • Subject: [mg116655] Re: Rational[a,b] vs Rational[1,2]
  • From: DrMajorBob <btreat1 at>
  • Date: Wed, 23 Feb 2011 05:22:42 -0500 (EST)

That seems reasonable, but like Andrzej, I don't see why anybody  
would/should type Rational[a,b] if he doesn't know what he's doing.


On Mon, 21 Feb 2011 23:21:07 -0600, Richard Fateman  
<fateman at> wrote:

> On 2/21/2011 6:26 PM, DrMajorBob wrote:
>> I think Mathematica expects us to create rationals in the usual way...  
>> by dividing integers. When we do, Mathematica removes common factors  
>> and can end up with an Integer, a Rational, Indeterminate, or  
>> ComplexInfinity.
>> If you try another method... good luck!
> A simple solution is to define Rational[a_,b_] := a/b /;   
> Or[Not[IntegerQ[a],IntegerQ[b]]
> wouldn't you agree?

DrMajorBob at

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