[Couenne] What is mean of the sentence that it does not understand ">", but only ">="?

[Pietro Belotti]

Lili,

most optimization solvers and modeling languages handle constraints of the 
form g(x)>=0, g(x)<=0, or g(x)=0, but not g(x)>0 or g(x)<0. Therefore, the 
problem you posted should be written as

min 0   
s.t. x1*x2+x3 >= 0
      x2+x1    >= 7.

Pietro

--
Pietro Belotti
Dept. of Mathematical Sciences
Clemson University
email: pbelott at clemson.edu
phone: 864-656-6765
web:   myweb.clemson.edu/~pbelott

On Tue, 15 Mar 2011, lili tan wrote:

> What is mean of the sentence that it does not understand ">", but only 
> ">="? I can ">=" in COUENNE user manual.
>
> --- 11年3月15日，周二, Stefan Vigerske <stefan at math.hu-berlin.de> 写道：
>
>> 发件人: Stefan Vigerske <stefan at math.hu-berlin.de>
>> 主题: Re: [Couenne] can COUENNE find a solution for the constraint satisfaction question?
>> 收件人: "lili tan" <tanlili2002 at yahoo.com.cn>
>> 抄送: couenne at list.coin-or.org
>> 日期: 2011年3月15日,周二,上午2:15
>> Hi,
>> 
>> > If I want to solve a constraint satisfaction question,
>> when I set objective function to a constraint, can COUENNE
>> find a solution for the constraint satisfaction question?
>> For example, objective function is min
>> 0   s.t. x1*x2+x3>0 and x2+x1>=7. Can
>> COUENNE find a solution (x1,x2, x3) that satisfy
>> x1*x2+x3>0 and x2+x1>=7?
>> 
>> Yes, maybe.
>> It does not understand ">", but only ">=".
>> And you only get a solution that satisfies the constraints
>> within some
>> tolerances.
>> It's numerics.
>> 
>> Stefan
>> > 
>> > 
>> >       
>> > 
>> > 
>> > _______________________________________________
>> > Couenne mailing list
>> > Couenne at list.coin-or.org
>> > http://list.coin-or.org/mailman/listinfo/couenne
>> > 
>> 
>> 
>> -- 
>> Stefan Vigerske
>> Humboldt University Berlin, Numerical Mathematics
>> http://www.math.hu-berlin.de/~stefan
>> 
>
>
> 
>
>
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