Group: sci.op-research
From: Wit Jakuczun
Date: Friday, March 21, 2008 3:30 PM
Subject: Re: Counting zero continuous variables

Dnia Fri, 21 Mar 2008 13:13:32 -0700 (PDT)
"xgeneral57@gmail.com" napisa=C5=82(a):

> 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?
>=20
Without introducing binary variables it is not possible. This means
you must switch to MIP. Moreover x(i)'s must be bounded.

Best regards
--=20
[ Wit Jakuczun ]
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