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Re: Problem with Inequalities

  • To: mathgroup at
  • Subject: [mg29706] Re: Problem with Inequalities
  • From: "Orestis Vantzos" <atelesforos at>
  • Date: Wed, 4 Jul 2001 03:08:30 -0400 (EDT)
  • Organization: National Technical University of Athens, Greece
  • References: <9hs0qo$br4$>
  • Sender: owner-wri-mathgroup at

Major misunderstanding ahead:
a>b tells Mathematica nothing about a and b; you actually question
Mathematica whether a is greater than b...if a and b are undefined then you
get your inequality back:
In: a>b
Out: a>b
If you want to "teach" Mathematica that a IS GREATER than b then do the
This defines an upvalue for the symbol a and sets a>b equal to True.
Note: I can't quite convince myself that this is "good" programming
practice. Apply at your own risk...

"Axel Dreher" <Mail at> wrote in message
news:9hs0qo$br4$1 at
> Hi,
> I'm desperately searching for help on my inequality question.
> How can I check for the truth of inequalities when I use variables
> instaed of numeric values?
> For example: a>b;TrueQ[a>b]
> does yield 'false' and for example a=1;b=0.5;TrueQ[a>b] yields 'True'.
> How do I have to tell the programm, that it should use a>b?
> Thanks for your help......
> Axel

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