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Re: [Help-glpk] Implementing conditional amount constraints using binar
Re: [Help-glpk] Implementing conditional amount constraints using binary variables
Wed, 3 Jun 2009 09:17:15 -0700
Both a and b can be bounded by a large M.
So let me reformulate my problem:
0 <= a <= M
if a > 0 : a=b
if a=0 : 0<=b<=M
On Wed, Jun 3, 2009 at 8:42 AM, Michael Hennebry <address@hidden>
How much greater?
On Tue, 2 Jun 2009, Yaron Kretchmer wrote:
I would like to implement the following condition on two variables:
*) If the amount of variable *a* is greater than 0, then the amount of
variable *b* needs to be equal to that of a.
Absent a finite number, I suspect that there is no MILP representation.
If there is only one such pair of variables,
the best solution might be to represent it as two separate problems.
*) If the amount of variable a is zero, then the amount of variable b is not
"Pessimist: The glass is half empty.
Optimist: The glass is half full.
Engineer: The glass is twice as big as it needs to be."