All Questions
Tagged with traveling-salesman-problem combinatorial-optimization
13 questions
6
votes
0
answers
104
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Knotted Traveling Salesperson route
Let us consider fixed points in space, if we apply the well-known Traveling Salesperson Problem algorithm, we get the shortest route. It can give a nontrivial knot in the three-space. The question is ...
- 121
2
votes
2
answers
163
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References for geometric properties of optimal Euclidean traveling salesman tour
Consider a finite set of points $V \subseteq \mathbb{R}^2 $ as a TSP-instance under the standard $\| \cdot \|_2$ norm. (TSP stands for traveling salesman tour.) We know that every optimal TSP tour $T$ ...
- 29
0
votes
0
answers
26
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Monotony of enforced subtour merging
Is it true that for a symmetric TSP instance in the sequence of edges generated by successively:
calculating the optimal 2-factor
adding cardinality constraints on the edgesets of the 2-factor's ...
- 13.2k
0
votes
1
answer
117
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Traveling salesperson problem algorithm [closed]
I was wondering something, let's say in a symmetric distance matrix of a sample of TSP, there was a sure algorithm that could remove between 30% to 80% of the values (distances) that wouldn't ...
1
vote
1
answer
115
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$\mathrm{LP}$ formulation for $\mathrm{k}$-$\operatorname{opt}$ moves
$\mathrm{k}$-$\operatorname{opt}$ moves are an idea to improve non-optimal Hamilton cycles in weighted symmetric graphs by exchanging $\mathrm{k}$ tour-edges with $\mathrm{k}$ edges that do not belong ...
- 13.2k
1
vote
1
answer
82
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Do we really need degree constraints for ILP formulations of TSP problems
The Dantzig-Fulkerson ILP-formulation of the symmetric TSP is
$$\min\sum\limits_{i=1}^{n-1}\sum\limits_{j=i+1}^n c_{ij}x_{\lbrace i,j\rbrace}\quad\text{s.t.}\\ \sum\limits_{j\ne i,\,j=1}^n x_{\lbrace ...
- 13.2k
0
votes
0
answers
40
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Subtour-gluing constraints for ILP formulation of TSPs
If one doesn't want to introduce additional variables to the ILP of a TSP instance, one has to add exponentially many so-called subtour-elimination constraints; in practical calculations subtour-...
- 13.2k
3
votes
0
answers
87
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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 $...
- 13.6k
0
votes
1
answer
54
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Relation of 1-trees to optimal tours
Question:
given a complete symmetric graph $G(V,E)$ with $n$ vertices and edges $e_{ij}$ having weight $\omega_{ij}$, does there always exists a vector of vertex potentials $(\pi_1,\,\dots,\,\pi_n)$ ...
- 13.2k
3
votes
1
answer
262
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What is known about this TSP variant?
Euclidian (planar) TSP asks for a tour with the minimum total length. The problem is known to be NP-hard. I am interested in the variant of finding a closed tour with the minimum enclosed area (...
- 2,993
2
votes
1
answer
139
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Description of Linear Time Algorithm for TSP in Halin Graphs
I am looking for a description of the linear time algorithm for the TSP in Halin graphs, that was given in
"G. Cornuejols, D. Naddef, and W.R. Pulleyblank. Halin graphs and the travelling ...
- 13.2k
3
votes
0
answers
145
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Hamiltonian cycle polytope for the hypercube graph
Let $Q_n$ denote the $n$ dimensional hypercube graph (i.e., graph formed from the vertices and edges of an n-dimensional hypercube). Denote the set of edges and vertices of $Q_n$ by $E_n$ and $V_n$ ...
- 393
2
votes
0
answers
119
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Corporate salesman problem
A salesman is employed by a large corporation. He has a $n$ cities to visit, connected by roads, forming a graph. But as travel takes a lot of time, he has to pick hotels between visits. He cannot ...
- 1,626