Questions about handling graphs in Mathematica, graph theory, graph visualization, GraphPlot, the built-in Graph type and the Combinatorica` package.

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1answer
72 views

Computing Domination Numbers of Graphs

Is there a way to get Mathematica to compute the domination number (size of the smallest dominating set) of a graph? There doesn't seem to be a direct command for this, so I'm not sure if there would ...
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1answer
71 views

Changing the size of arrows in a directed graph?

How can I change the size of arrows in a directed graph? By default, the arrows are too big and clutter the graph.
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0answers
62 views

Belief Network, Bayesian network

There is already a question about simulating Bayesian networks with Mathematica (Mathematica Package for Bayesian Networks). However, are there any packages or approaches which help in computing the ...
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0answers
28 views

“Partial” graph layout (with a fixed core)?

Is there a way to apply a graph lay out algorithm to a Graph object in such a way that a subset of its vertices and a subset of its edges are fixed beforehand, and ...
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0answers
46 views

Finding optimal inclusion cutoff to define subgraph of a “large” weighted graph

I have a weighted graph G with ~2.5K vertices and ~250K edges. (The edge weights are all in (0, 1), and the weight of each vertex is derived as the maximum of the ...
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0answers
57 views

Finding quasi-cliques

Is it possible to find quasi-cliques in a graph in Mathematica 10? I don't think it has been implemented, so are there any solutions to do this? Or do I have to export the graph data somehow and do ...
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1answer
48 views

How to invoke default VertexShapeFunction and EdgeShapeFunction from custom ones?

For this question, g is a Graph object (of order ~2K) such that the VertexWeight and ...
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3answers
79 views

How to control which nodes get placed at each radius with GraphLayout → “RadialEmbedding”?

I have a directed graph each of whose nodes belongs to exactly one of three groups: "sources", "sinks", and "both". As these names suggest, nodes in the "sources" group have only outgoing edges; ...
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1answer
161 views

Can degenerating Nicomachus' triangle down to $0$ area by using `Graph` be done?

I noticed a pattern in Nicomachus' Triangle that might be used to reduce the triangle to the number line. If the Edge size could be set to the absolute difference ...
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2answers
152 views

Speeding up the generation of all k-edge-coloring of a graph

A $k$-edge-coloring of a graph $G=(V,E)$ is a function from $E$ to $\{1,\ldots,k\}$, so in other words every edge of $G$ receives one of the $k$ colors available. (In particular, note that we are not ...
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2answers
205 views

Graph smoothing keeping vertices fixed?

Context Given a Graph like this one: ...
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0answers
43 views

NMinimize outside the feasible region

I got the following minimization problem. I get a solution if I set constraints1 := L.x >= y; and eliminate constraint 2 from my set of constraints. So ...
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0answers
68 views

Spread multiple edges by a specified scaled distance (Mathematica 10)

Is there way to spread multiple edges by a specified scaled distance for Graph function in Mathematica 10, something similar to MultiedgeStyle in GraphPlot for example, I would like to write: ...
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0answers
85 views

Using NMinimize to solve the Multi Commodity Flow problem

I have the following optimization problem and I was hoping to solve it with NMinimize. Unfortunately, I don't get the desired result. I would like to get an optimal vector for $d_{e}$. This is how ...
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0answers
124 views

Replace part in a matrix that matches specific pattern

I have the following problem. Given a matrix L which looks as follows, Matrix L is a link, route matrix. Further, I got the following vector (d), which indicates the demand per vertex combination. ...
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2answers
164 views

Finding the minimum vertex cut of a graph

Bug present in at least versions 9.0.1, 10.0.2 and 10.1.0 It seems that Mathematica is not correctly finding the smallest set of vertices that will disconnect a graph. Here is an example: ...
6
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0answers
72 views

Graph: PropertyValue changes and Dynamic

I almost never work with Graph in Mathematica but lately I helped someone with it. For this, I tried to make an animation using ...
8
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1answer
179 views

Vertex merging in graph?

Given a Graph such as the one produced with the following code ...
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1answer
52 views

Verticepair - route matrix

I have the following problem. I have two lists: list1 defines all possible commodities in a network g. E.g. Form vertex 1 to ...
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2answers
83 views

Equivalent of RadialOutside for Graph VertexLabels

I'm creating a circular graph and want the labels to be placed on the outside of the vertices in a circular manner on the outside of the graph. I've been playing around with the ...
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2answers
375 views

How to build a 3D graph from a 3D matrix?

Following this and that question and the corresponding answers, Mathematica can build 2D graph from 2D matrices. Question How to make the corresponding 3D graphs from 3D cubes? Attempt ...
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1answer
67 views

How to plot graphs with vertices positioned as spread as possible? [closed]

The following code, outputs the graph below: graphList = {{1, 2}, {1, 3}, {1, 4}, {2, 5}, {3, 6}, {4, 7}} Graph[UndirectedEdge @@@ graphList] Is there some way ...
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2answers
73 views

Getting FerrersDiagram to work

I am trying to generate FerrersDiagram (see http://reference.wolfram.com/language/Combinatorica/ref/FerrersDiagram.html), any clues to getting it to work? I get error message for the following: ...
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1answer
47 views

Create vector for each vertex in a network [closed]

I have a network with x vertices and I would like to create a vector with random numbers for each vertex in this network. I would like to generate this list and represent it in a table. Further, it ...
6
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1answer
312 views

Connect neighbouring points as list of segments in 2 D

Context I am interested in connecting neighboring points in 2/3D as list of segments. I am guessing this is something within the reach of graph theory, which is well implemented in mathematica. ...
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1answer
45 views

Unexpected behaviour with GraphIntersection and GraphDifference

I run into some unexpected behaviour of GraphIntersection and GraphDifference. Behaviour is the same for both so the example is only on the GraphIntersection: Suppose I have two lists of directed ...
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1answer
175 views

Why can't I export graphs with loops in V10?

bug persists through 10.1 (windows) I don't understand why the following does not work: ...
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1answer
95 views

Vertex Labelling and Word wrap

I am having trouble formatting vertex labels, explicitly adding line breaks to Vertex labels for word wrapping and other purposes. I have explored the pane option suggested here but when I include ...
2
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1answer
263 views

Dynamic graph construction and visualization (Watts' “Small Worlds” α-model)

I need some help in creating a Mathematica program for building and visualizing Watts' "Small Worlds" α-model. This is a variant of the more known (and much more simple) β-model (also known as ...
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1answer
87 views

Why Infinity edges with WeightedAdjacencyGraph [closed]

I can't understand why WeightedAdjacencyGraph wants Infinity weight when there are no edges between two nodes. In particular ...
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5answers
411 views

Is there a neat way to generate the odd set constraints matrix?

Given a undirected graph $G=(V,E)$, I am trying to generate a related matrix $M$, where columns are indexed by $E(G)$ and rows are indexed by all odd subsets of $V(G)$. I can finish this task using ...
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1answer
57 views

Graph labels are outside the plot area and other aesthetic considerations [closed]

The label of the rightmost element is clipped by the plot edge. ...
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2answers
72 views

Add weighted edge to a graph in Mathematica 8

Is it possible to add an edge with a specific weight to a Mathematica Graph object? The function EdgeAdd has no option for the weights, nor the ...
1
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1answer
53 views

Graph objects for LineGraph

When I enter for example G = Part[GraphData[10],1]; LG = LineGraph[G]; I get error message that LineGraph requires a graph ...
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2answers
196 views

Hasse Diagrams in Mathematica using an arbitrary relation

As a kludge to draw Hasse diagrams for an assignment, I wrote(based on this): ...
5
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3answers
220 views

Enumerating all connected graphs with 9 vertices

The version of my Mathematica is 10. I generate a connected graph with 9 vertices, but find that it is not included in Mathematica. ...
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0answers
74 views

Mathematically Eliminated in Baseball

Earlier today the Yankees were mathematically eliminated from the playoffs. Determining when this condition is satisfied for any given team is complicated but can be solved as a maximum flow problem, ...
2
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1answer
78 views

how to depict a network with a legend

Because my network nodes have real world names more than a few characters long, I'd like to label them with a shortcut, e.g., n1, n2, n3, ..., and put a legend on the side something like this: n1 - ...
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2answers
124 views

getting vertices in order from spanning tree

I've got spanning tree for some weighted graph (edges labeled 1-6) - for example: ...
2
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1answer
167 views

Finding Hamiltonian path in Graph

I have weighted, undirected full graph (generated from points in R^2), where weight between every two vertices are euclidean distance between corresponding pair of points. What I'm trying to do is ...
6
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1answer
176 views

Fractal dimension of a large networked molecular system

I am trying to determine the fractal dimension of this complex biomolecule (figure attached). Any clues as to how this can be done. In trying to determine this quantity, I wonder how its ...
1
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1answer
122 views

Planar graph layout

Mathematica supplies planar graph layout, which draws a nice picture of a planar graph, but is there any way to get one's hands on the layout? For example, to find its faces (complementary regions)? ...
5
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3answers
101 views

GraphIntersection Problem

I Have a problem when plotting 2 functions. I want to find out where the two graphs intersect eachother. That said, I want the coordinates (x, y) of the point. ...
2
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1answer
152 views

Dynamic process on graph

I have a question, which I failed to find an answer to myself. I'm a casual user of Mathematica, but do have some knowledge about Dynamic module and other "Advanced" features. My problem is ...
2
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1answer
54 views

Mathematica 8: EdgeList and CommunityStructureAssignment shadowing problem

I'm facing some issues when trying to use the CommunityStructureAssignment function from the GraphUtilities package in Mathematica 8. I'd like to output a ...
5
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2answers
163 views

Graph expansion on Mathematica

Is there a way by which Mathematica can be given a graph as an input and be asked to find its expansion? Note: By "expansion" I mean the quantity called "isoperimetric number" or "Cheeger constant", ...
9
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4answers
246 views

Multiple Forms of Transportation Between Cities

I want to be able to show different connections between cities based on modes of transportation. For instance, you could walk to any city, but it would take a long time, you could take a train, but ...
13
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6answers
607 views

Finding all paths of certain length between vertices in path graph, non-simple ones too

First I will tell you what my ultimate goal is, because maybe there's another way of doing it other than what I am trying. I need a list of all $(a_1, a_2, \ldots, a_N)$ tuples that satisfy certain ...
2
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1answer
133 views

Creating an Adjacency Matrix to connect an undirected network

I used the locator pane to map a network, specifically the Maryland Power Grid. What I would like is to have some sort of numbering of the vertices on the unconnected network, how to make an adjacency ...
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0answers
39 views

Graph embedding and edge weights [duplicate]

Does functions like GraphPlot take in to account edge weights in case of springelectrical embedding? In case of spring electrical embedding I expect the vertices connected by heavy edges to be pulled ...