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Topic: disjunctive constraints in integer linear programming
Replies: 9   Last Post: Apr 14, 2013 2:43 AM

 Messages: [ Previous | Next ]
 d.info.sign@gmail.com Posts: 2 Registered: 4/11/13
Re: disjunctive constraints in integer linear programming
Posted: Apr 11, 2013 5:18 PM

On Thursday, April 11, 2013 3:47:18 PM UTC-4, quasi wrote:
> d.info.sign wrote:
>

> >
>
> >I have an integer linear programming problem as follows:
>
> >
>
> >The constraints are either
>
> >
>
> >x >= 0
>
> >y = u
>
> >z = x + v
>
> >
>
> >or
>
> >
>
> >x < 0
>
> >y = u - x
>
> >z = v
>
> >
>
> >where y, z, u, v range over non-negative integers. There are
>
> >other unrelated constraints associated with u, v, y, z.
>
> >
>
> >What's the most simple way to encode the disjunctive case?
>
>
>
> Why not just run two separate linear programs and choose
>
> whichever of the two optimal solutions offers a better value
>
> for the objective function?
>

Unfortunately we can't. This form of constraints occur often in our system. The approach you suggested would lead to exponential enumeration.

Thanks!

Date Subject Author
4/11/13 d.info.sign@gmail.com
4/11/13 quasi
4/11/13 d.info.sign@gmail.com
4/12/13 quasi
4/11/13 William Elliot
4/12/13 RGVickson@shaw.ca
4/12/13 quasi
4/13/13 RGVickson@shaw.ca
4/13/13 RGVickson@shaw.ca
4/14/13 quasi