5
votes
Accepted
The linearization of the (Iff-and-only-Iff) expression
One possible way to linearize such a constraint would be by dividing this expression into four parts and then linearizing each of which separately.
$$ Iff \quad (w=1) \rightarrow (x \rightarrow y) \...
- 7,271
4
votes
The linearization of the (Iff-and-only-Iff) expression
@A.Omidi gave a nice derivation using conjunctive normal form. In this case, the big-M approach with $M=1$ yields the same formulation:
$$w = 1 \implies x=y$$
can be enforced via
$$-(1-w) \le x-y \le ...
- 27.1k
2
votes
multi-commodity flow vs integer programming
I am a bit confused about the 2nd constraint.
Nevertheless in the derived STU (combination of show type, start time, end time), exclude combinations like (o,16,19), (o,17,20)..(m,18,19) etc because ...
- 2,527
1
vote
Array of string in OPL
.mod
{string} cluster=...;
string darkstore [cluster][1..4]=...;
string demandpoint [cluster][1..4]=...;
.dat
...
- 3,982
1
vote
Optimization solver that satisfies variable values within set membership
AMPL automatically linearizes var purchase {CUSTOMER} in VALUE; where VALUE is a set of numbers. The linearization creates some ...
- 618
1
vote
Maximization problem with preferences on variables
How is this following constraint
Either
$b_z + y \le b_x+z +b_y\le x + b_z +yb_y$
Or let's break it
$b_x+z \le x + b_z$
$b_z + y \le z +b_y $
- 2,527
1
vote
How to find the maximizing number of expected delivered units of a probabilistic minimum cost flow problem?
Since you seem to have figured out a distribution for minimum cost flow (appears like Log-normal) you can try 2- stage stochastic programming using SAA techniques. LINDO Systems or model offers a ...
- 2,527
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