Skip to main content

All Questions

Filter by
Sorted by
Tagged with
0 votes
0 answers
145 views

Bound on solutions of $Ax \ge b$

Let $A \in \mathbb{Z}^{m \times n}, b \in \mathbb{Z}^{m \times 1}$. One can show that if there is a solution of $Ax \ge b, x \in \mathbb{R}^n$ then there is one such that $\|x\|_{\infty} \le c (\|A\|_{...
user1868607's user avatar
19 votes
4 answers
1k views

Applications of linear programming duality in combinatorics

So, I know that one can apply the strong LP duality theorem to specific instances of maximum flow problems to recover some nontrivial theorems in combinatorics, such as Hall's theorem, Koenig's ...
amakelov's user avatar
  • 997
0 votes
0 answers
165 views

Minimum circumscribed ellipsoid of $\mathcal H$-polytope

Given matrix $A \in \mathbb{R}^{m \times n}$ and vector $b \in \mathbb{R}^n$, consider the $\mathcal H$-polytope $P$ defined as follows $$ P := \left\{ x \in \mathbb{R}^n : Ax \leq b \right\} $$ I ...
Daniel Turizo's user avatar
4 votes
1 answer
204 views

Reference: Packing under translation is in NP

I am looking for a reference for a result that I am aware of. Let me describe the result. Given a polygon $C$ and polygons $p_1,\ldots,p_n$, it can be decided in NP time, if $p_1,\ldots,p_n$ can be ...
Till's user avatar
  • 479
17 votes
3 answers
6k views

The cone of positive semidefinite matrices is self-dual? (reference needed)

I'm seeking a reference for the following fact. The cone of positive semidefinite matrices is self-dual (a.k.a. self-polar). This result is relatively easy to prove, has been known for a long time,...
Louis Deaett's user avatar
  • 1,513
3 votes
0 answers
87 views

Additional symmetries of the Traveling Salesman Polytope

Given the complete graph $K_n=(V,E)$, the Traveling Salesman Polytope is a convex polytope in $\Bbb R^E$ obtained as the convex hull of the indicator vectors of (edge-sets of) Hamiltonian cycles in $...
M. Winter's user avatar
  • 13.6k
2 votes
1 answer
509 views

Under what condition does Courant–Fischer–Weyl min-max principle hold in general?

From Wikipedia: Let $A$ be an $n \times n$ Hermitian matrix. As with many other variational results on eigenvalues, one considers the Rayleigh–Ritz quotient $R_A : \mathbf C^n \setminus \{0\} \to \...
Fraïssé's user avatar
  • 155
7 votes
1 answer
374 views

Sampling uniformly from the vertices of a polytope

I'm looking for a reference on how to sample uniformly (and preferably efficiently, elegantly, etc.) from the vertices of a polytope. I gather that enumerating vertices is hard. I also note the MO ...
Steve Huntsman's user avatar
2 votes
0 answers
148 views

Generalization of Farkas' Lemma to Hermitian Matrices

I recently stumbled upon a well-known version of Farkas' Lemma which, roughly speaking, I would like to generalize from real vectors to hermitian matrices, as it seems promising for something else I ...
Frederik vom Ende's user avatar
3 votes
1 answer
266 views

Strong polynomial algorithm for linear programming

What is the current state of finding a strong polynomial algorithm for linear programming? Is there any reference?
Hao Yu's user avatar
  • 781
2 votes
2 answers
3k views

Linear programming with infinitely many constraints

I wish to study the following linear program $$\begin{array}{ll} \text{minimize} & \mathrm c^{\top} \mathrm x\\ \text{subject to} & \mathrm A \mathrm x = \mathrm b\\ & \mathrm x \geq 0\...
user3433489's user avatar
2 votes
3 answers
753 views

Reference Request for Integer factorization with LP/ILP

Have there been attempts to factor integers with Linear Programming? Searching the internet suggests that for Integer Factorization only Number Theoretic algorithms, like sieves, are taken into ...
Manfred Weis's user avatar
  • 13.2k
5 votes
1 answer
183 views

Resource Constrained Routing with Refueling

What are good algorithms (resp. models) for calculating optimal or near optimal routes while taking into account fuel consumption, options for refueling and, limited tank capacity? Especially modeling ...
Manfred Weis's user avatar
  • 13.2k
5 votes
2 answers
2k views

Bounding the minimal maximum norm of a solution of a linear system.

I would be grateful for pointing me out a reference to some general bound on the $\ell_{\infty}$ norm of a solution of a linear system. To be specific, suppose that we have an underdetermined linear ...
user3645's user avatar
  • 191
4 votes
0 answers
203 views

$\ell^1$-norm minimization duality

I am looking for an explicit description and discussion of the dual of the $\ell^1$-norm minimization problem $\lVert A x\rVert_1\to\min$, where $A$ is a matrix, and $x$ belongs to the $n$-simplex $\...
R W's user avatar
  • 17k
0 votes
0 answers
46 views

linear inequalities and reference request

I have proved and am using the following simple lemma in my current research problem: Let $\{a_1,...,a_m\}$ and $\{b_1,b_2,...,b_n\}$ be set of positive numbers such that $\sum_{i=1}^m a_i < \sum_{...
GA316's user avatar
  • 1,269
3 votes
1 answer
340 views

Name search for special Linear Integer Program

I am looking for a name for the following question in literature! (and if you know it, then it would be great) I couldn't find it and due to wide audience here, presumably you know more. Thank you $...
JensLans's user avatar
2 votes
1 answer
301 views

books on very large scale linear optimization

Recently in my material science research, I have encountered problems of very large scale linear optimization. I read the introductory book "Introduction to Linear Optimization (Athena Scientific ...
user40780's user avatar
  • 867
4 votes
1 answer
2k views

solving multiple linear programming problems with the same set of constraints

Hi, I need to solve a set of linear programs of the form: Problem $i$: $\quad \max c_i \cdot x$ s.t. $ A x \leq b$. The $c_i$'s are different vectors so each problem has a different objective ...
Or Zuk's user avatar
  • 560
1 vote
0 answers
493 views

Complexity of Nested Linear Optimization

My question is motivated by the fact, that among other ways, it is possible to restrict a variable to two discrete values, e.g. the prototypical $0$ and $1$, via an optimization constraint: $$\max(\...
Manfred Weis's user avatar
  • 13.2k
2 votes
0 answers
39 views

In what paper was the shrinkage parameter introduced to the nelder-mead simplex direct search algorithm?

I have read lots of papers referencing a 4th shrinkage parameter when talking about the Nelder Mead Simplex method. However, I cannot see any shrinkage parameter in the flow chart of the original ...
Craig's user avatar
  • 21