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From: "xgeneral57@gmail.com"
Date: Friday, March 21, 2008 3:40 PM
Subject: Re: Counting zero continuous variables
From: "xgeneral57@gmail.com"
Date: Friday, March 21, 2008 3:40 PM
Subject: Re: Counting zero continuous variables
On Mar 21, 4:30=A0pm, Wit Jakuczun
> Dnia Fri, 21 Mar 2008 13:13:32 -0700 (PDT)
> "xgenera...@gmail.com"
>
> > I have a set of continuous variables x(i), i=3D1,.., N where x(i) can be=
> > negative, zero or positive. I'm trying to count, in some way, how many
> > of x(i)'s are exactly zero. Is there any way to do so using linear
> > constraints?
>
> Without introducing binary variables it is not possible. This means
> you must switch to MIP. Moreover x(i)'s must be bounded.
>
> Best regards
> --
> [ Wit Jakuczun =A0 =A0
> [ WLOG Solutions =A0http://www.wlogsolutions.com]
x(i)'s ae actually bounded above and below: LB(i) <=3D x(i) <=3D UB(i).
But the problem is that x(i)'s can be either positive or negative.
