158 views

### How to write an OR constraint in MILP?

I want to write a constraint with ORs in a MILP. In particular, the following: $$x \ge c \lor x \le -c \lor x=0,$$ where $c$ is just a real number. Can anyone give me some hints?
340 views

### How to model equality in Integer Linear Programming

How to implement v=(a==b) using Linear Programming? $$v= \begin{cases} True, a=b\\ False, a≠b\\ \end{cases}$$ Until now I tried the big M-Method. To show a≤b: $$a-b+Mv≤M$$ $$-a+b-Mv≤-1$$ To show ...
13 views

### Relating indexes for parameters and variables

I am trying to solve a referee assignment problem, but I simply can't think of a way to relate my variable to one of the parameters, and I hope that someone in here can help. I have the following ...
• 45
89 views

### Objective function and constraint satisfaction over a set of multi-attributes elements

I'm looking for an approach to solve a problem consisting of maximizing an objective function over a set of discrete elements, while respecting a set of constraints. To illustrate my point, I'll try ...
• 203
515 views

### NP-completeness proof via reduction

I'm aware that 0-1 integer programming problem is NP-complete, where the problem is stated as: Given some integer matrix A and some integer vector b, determine whether there exists a vector x ...
• 473
2k views

### Express XOR with multiple inputs in zero-one integer linear programming (ILP)

In the below post, it is explained how to express xor of two variables as linear inequalities. Express boolean logic operations in zero-one integer linear programming (ILP) Naturally, the xor of ...
335 views

### Integer Linear programming formulation if then condition

I want to create constraints such that I can implement the following condition: Let A be an integer variable >= 0 with an upper bound of 12 I want to introduce the following variable B also an ...
2k views

• 143
42 views

### IF THEN condition in Linear Program

I have the following condition in an LP problem. I have a variable $x_i \in i = 1,2,..7$ and I need to constrain the problem via: if $x_1$ >5 then $x_2 \leq 30$ I'm stumped on how to formulate that ...
42 views

### Formulating if-then constraints in linear binary programming

From a stock of various computer accessories of different brands, the optimization problem requires deciding to keep or discard products. The decision should be made maintaining the following if-then ...