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

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How to query W|A, to get a list of asymmetric, bicubic and $3$-edge colorable graphs? [closed]

I'm interested in finding graphs with certain properties, like the smallest cubic bipartite asymmetric graph. While working on a related graph-theoretic problem, concerning edge-colrings, I came along ...
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1answer
50 views

FindCycle not working as expected for multigraph

Say I have a simple multigraph like so: edges = {DirectedEdge[a, b], DirectedEdge[b, c], DirectedEdge[c, a]}; g = Graph[Join[edges, edges]] ...
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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 ...
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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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1answer
59 views

How should my data be formatted for use with BetweennessCentrality?

A few weeks ago I asked this question. I am trying to upload my data which is an adjacency list for an undirected, unweighed graph and find the betweenness centrality. At the time I tried to use the ...
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1answer
184 views

Why is my PageRank result in Mathematica converging this way?

I am using this technique to find the PR of these 3 pages. It converges to something it shouldn't be. I tried the same iteration in Java and 2 pages come up with 1.333 and the other one as 0.666. ...
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1answer
122 views

Testing Equality Expression?

Even if in Graph[{1 -> 2}] == Graph[{1 \[DirectedEdge] 2}] the answer is True ; but why MMA doesn't show the result of the ...
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1answer
133 views

How can I extract coordinates of the nodes of my graph?

I have this output for my graph. ...
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1answer
107 views

How does SocialMediaData determine vertex size

How does SocialMediaData determine the size of graph vertices, e.g. on what does the vertex size depend in, say, a Facebook friend network graph?
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21 views

How to make the vertices move with the VertexRenderingFunction graphics when clicking and dragging vertices of a layered graph [duplicate]

I have read the suggested similar question here: VertexRenderingFunction (or EdgeRenderingFunction) with movable nodes? and Mr. Wizard's solution. Please could someone help me to apply his method to ...
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35 views

Is it possible to visually edit a graph?

Given a graph, obtained by something like CompleteGraph[5], can I somehow add/remove edges/vertices visually? Or is the only alternative to transform it via ...
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42 views

Trying to write a program to find an approximate harmonic function on a given graph using relation method

So given an undirected graph with two vertices that have fixed values assigned to them, a harmonic function is a function that assigns values to all other vertices such that the value assigned to each ...
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0answers
35 views

Error with AppendTo [duplicate]

I am trying to write a function that builds a graph, or - better said - adds a layer of leaves to a pre-existing graph. Basically, I hand to the function three lists. ...
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0answers
43 views

Draw a single disconnected vertex [duplicate]

I am just started using Mathematica. I am trying to split my graph into two sets. 1. How does Mathematica split the graph into 2 subgraphs (connected or disconnected)? 2. How can I draw a graph with ...
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0answers
54 views

Is it possible to use EdgeCapacity in FindMinimumCostFlow?

I'm having trouble getting the EdgeCapacity feature in FindMinimumCostFlow to work. I have attached a simple example. We have a simple graph of four vertices. There are two paths from the "source" ...
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0answers
63 views

What graph distributions are available in Mathematica?

Where can I find a list of all the graph distributions available in Mathematica?
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0answers
47 views

Transform NMinimze into LinearProgramming formulation

I have the following maximization problem that I currently try to solve with Minimize/NMinimize. Unfortunately, this kind of solution method takes really long for large systems of equations and ...
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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
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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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, ...
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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 ...
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0answers
34 views

Find set of subgraphs of g1 isomorphic to g2 [duplicate]

I would like to find all the subgraphs of a given graph g that are isomorphic to the graph h. My current code doesn't work how it should. Many solutions are missed and I think something is ...
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0answers
58 views

how to rewire the minimum number of edges in a disconnected bipartite graph, so to transform it in a connected one

Consider an incidence matrix A for a bipartite graph (Aij=1 if node i of group 1 and node j of group 2 are connected). A is not symmetric. Assume that A is disconnected or only weakly connected, i.e. ...
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99 views

Centrality measures and normalisation

Are centrality measures normalised in Mathematica 9? Only ClosenessCentrality is normalised. How I can normalise other centrality measures notably ...
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46 views
-1
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1answer
70 views

How to draw a network from a dataset reporting the labels of nodes of every link?

I have a dataset in format .txt of a directed network, containing a matrix A of dimension ...
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0answers
16 views

How can I solve this problem in graph theory? [on hold]

How can I show that d(X) + d(Y ) = d(X ∪ Y ) + d(X ∩ Y ) + 2e(X \ Y, Y \ X) if G be a loopless graph and X and Y be subsets of V ?
-3
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1answer
55 views