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

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2
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1answer
238 views

Want to label vertices of a graph and manually move them around

I would like to plot a graph in such a way that The vertices are labeled using labels that I've given them, rather than just their number, I can manually move the vertices around. In the code ...
2
votes
1answer
64 views

Reversibly abstracting a list of strings as a graph object where vertices represent strings and edge connect pairs of strings based on various tests

Imagine I provide you a list of arbitrary strings, say: Map[StringJoin, Tuples[{"0", "1", "2"}, 4]]. I'd like to abstract these strings as a graph object in ...
2
votes
1answer
664 views

Create a graph from KML file

I'm wondering how I can take a .KML (Keyhole Markup Language) file and convert/express it as a graph for use in Mathematica. Even just in general, is it possible to convert a KML file to a graph? I'm ...
2
votes
1answer
435 views

GraphPath: *all* shortest paths for 2 vertices, edge lengths negative

Mathematica uses Bellman-Ford to find a shortest path between two vertices when the edge lengths are negative: ...
2
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1answer
109 views

PermuteSubgraph not working? (Combinatorica)

I am trying to write a code to perform the QAP partialling analysis (here's a paper to know more) but the part in which I "scramble" the graph with PermuteSubgraph does nothing, I am actually not ...
2
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1answer
140 views

Is it possible for me to explicitly specify a point list for SpatialGraphDistribution?

The function RandomGraph[SpatialGraphDistribution[n, r]] generates a random geometric graph over $[0,1]^2$ where vertices are connected if they are within a ...
2
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1answer
159 views

VertexList ordering of a simple graph

Given a simple graph like g=Graph[{b -> c, a -> b}] I would like to have f[g] resulting in ...
2
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1answer
334 views

Changing some stuff to Kruskal's Algorithm

I'm trying to modify this algorithm: http://demonstrations.wolfram.com/ConnectingTownsUsingKruskalsAlgorithm/ The thing is that I want to receive a Graph (declared outside, with all its vertex, edges ...
2
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0answers
110 views

How to make a flowchart? [closed]

I'd like to make a flow chart in similar to this: I think it's more of a layout and stylistic question for a graph - how to style a graph with labeled edges and vertices so that it looks like a ...
2
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0answers
78 views

How do I get all possible paths in terms of edges, and not vertices in Mathematica?

Suppose I have an undirected graph ...
2
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0answers
37 views

Algorithm to determine if two colored graphs are isomorphic? [duplicate]

I have two (vertex-)colored graphs. I want to determine if they are isomorphic, with the condition that the isomorphism respects the colors of the vertices. Moreover, I want the algorithm to output ...
2
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0answers
89 views

Graph, overlapping vertexlabels

The graph I create is based on more then 1000 different word-combinations. A example looks like this: text = {{word, word1}, {word1, word2}, {word1, word3}, {word,word4}, {word,word5}, ...
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0answers
48 views

Custom graph distribution

I am working with random graphs a lot. It's quite easy to describe random graph using, adjacency matrix or just a list of edges. However I am thinking that I might benefit from describing random ...
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0answers
54 views

Replicate CommunityGraphPlot as a Graph

Is it possible to format a Graph object in a similar way to CommunityGraphPlot, but retain it as a Graph? I've been playing with FindGraphCommunities but I'm obviously missing some of the ...
2
votes
1answer
269 views

Distinguishing left from right adjacent triangles in triangle mesh [closed]

What I'm trying to do: I'm trying to create a path-drawing function which will produce a path like the one I-P in the diagram below. The way this path was generated requires me to swap between the ...
2
votes
0answers
59 views

Bugs in VertexContract function?

I think there may be two bugs in the VertexContract function: 1) The updated graph does not include reasonable edgeweights 2) The function does not actually reduce the number of vertices in the ...
2
votes
1answer
47 views

VertexConnectivity and FindVertexCut disagree [duplicate]

I'm trying to use Mathematica to compute the minimal vertex cut for graphs. From what I understood, VertexConnectivity of a graph should correspond to the number of vertices in the minimal vertex cut. ...
2
votes
0answers
96 views

Is there a minor bug in Neal Alexander's TopologicalSortAll[]?

There is an amazing answer to this question: All possible topological orderings of a graph By Neal Alexander. However, as user "dark blue" (I am not this user) notes: ...
2
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0answers
70 views

Choosing a List as VertexWeight for a TreeGraph

I would like to map every vertex of my TreeGraph to an List. ...
2
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0answers
101 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 ...
2
votes
1answer
385 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 ...
2
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0answers
76 views

What Algorithm Does Mathematica use to Calculate Betweenness Centrality for Unweighted Graphs?

I recently asked this question on the Mathematics SE. Does anyone know, as a follow up, what algorithm Mathematica uses to calculate the betweenness centrality vector (of $N$ elements) for an ...
2
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0answers
85 views

Get correlation matrix when using FindGraphCommunities

Does somebody know how to get the correlation matrix when using FindGraphCommunities (Social Network analysis) using the "Spectra" option? Can somebody tell me as ...
2
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0answers
58 views

How to use Automorphisms[] on a graph? [duplicate]

I am having difficulty mixing the new post-Combinatorica graph data structure, with functionality apparently only in Combinatorica. I have constructed a graph using ...
2
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0answers
329 views

Why my Mathematica 9.0.1 wont work with some samples of Mathematica in Graph Theory?

Bug introduced in 9.0 and fixed in 10.0 FindMinimumCostFlow is introduced in 9.0. I updated my Mathematica recently to 9.0.1 cause the previous version was ...
2
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0answers
227 views

Fast calculation of commute distances on large graphs (i.e. fast computation of the pseudo-inverse of a large Laplacian / Kirchhoff matrix)

I have a large, locally connected and undirected graph $G$ with $\approx 10^4$ vertices and $\approx 10^5$ to $\approx 10^6$ edges. Moreover I can bound the maximum vertex degree as $Q_{max}$. I ...
2
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0answers
120 views

Strange double evaluation using MorphologicalGraph

(MMA 9.0.0 on Mac OS/X 10.8) Please consider the following snippet (this is as SMALL as I could make it -- my attempts at making a smaller repro-case eliminated the effect that I am investigating) ...
2
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1answer
204 views

How to preserve graph properties under subgraph in MMA9 [duplicate]

Possible Duplicate: Preserving labels when using graph functions I'm using g = SocialMediaData["Twitter", "FriendNetwork"] to get a nice graph with ...
2
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0answers
247 views

How to predict some constant number of values with NeuralNetworks

Example: << NeuralNetworks` data = {Sin[#]} & /@ Range[0, 4 Pi, 0.5]; learn = data[[1 ;; 15]]; Now, lets fit our neural network: ...
1
vote
2answers
751 views

Coloring vertices using GraphPlot

I have the following problem: I used GraphPlot to plot my adjacency matrix. I divided my nodes in three groups: ...
1
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1answer
296 views

How do I create a graph with randomly directed edges starting from a undirected graph?

I have an undirected graph $G$. How would I randomly assign directions to some fraction $p$ of the edges? How might I do this efficiently / quickly provided I have a large graph structure? For ...
1
vote
1answer
61 views

Unexpected AdjacencyMatrix output [duplicate]

I have a directed graph with this Edgelist defined as follow: ...
1
vote
3answers
107 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; ...
1
vote
1answer
322 views

Adjacency Matrix for an Undirected Graph

Here is an undirected graph ...
1
vote
2answers
271 views

Number of edges to each polygon of a graph constructed from an image

I have an image which looks like from How to convert an image to a graph and get the positions of the edges? which by using MorphologicalGraph becomes a graph ...
1
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3answers
55 views

How to draw graph with named vertices by adjacency matrix?

I have the adjacency matrix of graph and I want visualize this graph. I tried: ...
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2answers
146 views

Styling the edges of a graph according to the multiplicities of the edges

I used the following code to make a simple triangle, in which the nodes have different effects each other: ...
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2answers
95 views

Graph: ordered vertices

I have tried things like ...
1
vote
1answer
387 views

How to construct a graph from a list of edges

I have a list of pairs of numbers, representing connections between objects in the real world. Each number is the identifier of an object, there are gaps in the range from the smallest number to the ...
1
vote
2answers
649 views

Swapping elements of list

Say I have a directed graph inputted in the following format in Mathematica: g = {{1, "a", 2}, {2, "b", 1}} I'd like to plot this graph using ...
1
vote
2answers
166 views

Converting polygon to graph in V7

I've unsuccessfully tried many ways of converting polygon points into a graph using Mathematica 7, and I am frustrated. I looked at this post, but it doesn't work: ...
1
vote
1answer
145 views

Is there an easy way to specify an arbitrary two-dimensional Polyomino tiling in Mathematica 8.0?

Is there an easy way to generate an arbitrary two-dimensional Polyomino tiling: http://en.wikipedia.org/wiki/Polyomino? Specifically, I would like to generate an array of integer coordinates, for ...
1
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1answer
40 views

None connected graphs for n=59? [closed]

For some reason GraphData["Connected", 59] gives no graphs, is this a bug?
1
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1answer
29 views

WeaklyConnectedGraphQ evaluates to False. Is this the expected result?

Take the simple graph {1->2, 2->3, 3->1}: TreePlot[{1->2,2->3,3->1}] I would expect that ...
1
vote
1answer
87 views

LayeredGraphPlot: how to specify edge endpoints?

What directive within the LayeredGraphPlot command specifies where the edges attach to vertices? For example, instead of the left output below, I'd like to have the right one. ...
1
vote
1answer
177 views

Importing adjacency matrix from file of 0/1 arrays

Is it possible to import adjacency matrix for graph representation, from simple text file with NxN (rows x columns) of 0s/1s: 0 1 0 0 1 0 1 1 0 1 0 0 0 1 0 0
1
vote
1answer
110 views

Extracting a single weakly connected component from a network of many weakly connected components?

Hello Mathematica friends! I've got a network with thousands of edges and vertices, but not all in one connected component. I'm trying to extract specific connected components from the network, and ...
1
vote
1answer
729 views

Plotting a network or a graph with given coordinates for vertices

I'm new to Mathematica yet have coded a lot in MATLAB. Currently I'm working on a network simulation. My model is implemented in MATLAB, but I need to port it to Mathematica. Here is my question: ...
1
vote
1answer
259 views

How can I create Arguments Maps with Mathematica's graph functions?

I am relatively new to Mathematica, and I would like to know how I could use it to represent an Argument Map, such as those that you generate on online tools such as http://debategraph.org. The ...
1
vote
1answer
312 views

Problem setting up edge rendering function

I have a graph, and I want my EdgeRenderingFunction to colour the edges based on the vertex they originate from. In this toy example, I'm trying to get the edge ...