# Tag Info

## New answers tagged modeling

5 votes

### Additional resources for this type of problem formulation

The model looks really linear to me. After substituting out $V_{i,j}$ you have basically terms $x_{i,j}\cdot x_{k,j}$. Solvers may linearize that automatically or you must do it yourself. My guess is ...
• 1,571
2 votes

### Multiprocessor Scheduling Problem: How to modify some constraints after variable changing?

The condition (*), that every job is assigned to exactly one machine, simply requires $$\sum_{i=k}^n z_{i,k} \ge 1 \quad \forall i=1,\dots,n.$$ That ensures that every job belongs to a cluster. It ...
• 29.7k
2 votes
Accepted

### Disjunctive Constraint , Using Binary Variable to Replace a If or condition

The usual approach to this requires that $b$ be bounded, say $L \le b \le U$ for some constants $L$ and $U.$ You can come close to what you want with the following: $$b \ge \pi (1-q) + L q$$ b \le \...
• 29.7k
4 votes

### How to model Max-Cut as ILP

To start with maxcut, you can start with the maxcut example in how to with OPL ? ...
• 3,517
4 votes
Accepted

### How to model Max-Cut as ILP

Let $V$ and $E$ be the sets of vertices and edges respectively. Define a binary variable $x_v$ for each vertex $v\in V$ to be 1 if the vertex is on the "left" side of the cut and 0 if it is ...
• 29.7k
3 votes
Accepted

### cpu time in docplex

Yes , that's CPU time. If you want real time then use the python time module
• 3,517
9 votes
Accepted

### How to Model Path Being Only Through Adjacent Cells

A standard approach for modeling a path from source $s$ to sink $t$ in a directed graph with node set $N$ and arc set $A$ is to let continuous variable $x_{ij} \ge 0$ represent the flow along the arc \$...
• 22.2k

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