Top new questions this week:
|
|
I know that the Column Generation algorithm delivers an exact solution when you are solving a linear programming optimization problem. I want to know that, does this column generation approach deliver ...
|
|
I am trying to model a min-max VRP problem with multiple delivery vehicles and I have come up with a model using branch and cut but I do not think it is strong enough as it takes lot of time to ...
|
|
I am trying to solve a linear program that is identical to a min-cost flow problem, except for a difference in the flow-conservation constraint.
Instead of the summed outgoing flow equaling the summed ...
|
|
I want to solve a VRP with a column generation algorithm. The objective of the problem is makespan minimization. In more detail, I want to minimize the arrival time of the last vehicle in the depot. I ...
|
|
I have implemented a set of "or" constraints in my ILP using binary decision variables (as in this method). It works fine for smaller problems, but when I try to increase the number of ...
|
|
I built a solver for a classic scheduling problem. It has some exact methods and some heuristics methods.
I want to judge the quality of the work beyond time efficiency and solution quality.
For ...
|
|
Let's say you have a list of at most N Jobs to be done which are coming in a stream. There are two kinds of systems that can do the job:
System 1: A very fast system, which however, only does the job ...
|
Greatest hits from previous weeks:
|
|
I have a problem that I have already posted elsewhere in OR.stack, but the question is focused around a large binary MILP (about 1 million decision variables). Ultimately, I am more time constrained ...
|
|
I have a constraint that I believe to be convex and not affine which I think means that I can implement a relaxation. I will first define the full constraint, and then build up my (informal) reasoning ...
|
|
I have been accepted for an internship for 6 months. The aim of this internship is to implement a "generic" solver for scheduling/production planning problems. This solver will bill a small prototype ...
|
|
About Polyhedra, Polyhedron, Polytopes and Polygon, what do they mean in the context of linear programming and what is the difference between them?
|
|
I noticed the similarities between KKT and complementary slackness, but I do not fully understand it.
|
|
Suppose we have a binary or continuous variable $x$, a binary variable $y$, and a constant $b$, and we want to enforce a relationship like
If $x \gtreqless b$, then $y = 1$.
How can we write ...
|
|
When I have to write the formulation of an IP, I usually have the choice between writing $i\times j$ binary variables with two indices such as $ x_{i,j} $ or, writing $j$ integer variables $x_i$.
Is ...
|
Can you answer these questions?
|
|
Suppose a minimum weighted independent set in a conflict graph with $n$ vertices. The basic version is where each vertex $i$ is associated with a weight $c_i$. i.e., there is a vector $C$ for the ...
|
|
I am familiar with how to use ompr::MIPModel but I am trying to learn how to use MILPModel to take advantage of the model build speed. A simplified version of my model is below. I have two decision ...
|
|
If I can show a polyhedron Y is an extended formulation of polyhedron X and every extreme point in Y is integral, does that automatically imply the projection of Y onto the variable space of X gives ...
|
