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

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9
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1answer
264 views

Binary decision diagrams (BDD)

I would like to use Mathematica to help me simplify a given Binary Decision Diagram (i.e. pick the optimal variable ordering). I don't seem to find anything at all on the topic, although it is ...
8
votes
3answers
552 views

How can one draw a network with nodes and links in a grid shape?

I'd like to be able to use MMa's graphics to make something like this which I know must absolutely be possible (and probably easy) with MMa. I don't actually even need different colors (though ...
8
votes
2answers
1k views

Dynamic graph visualisation using JLink/Java and GraphStream

Visualising the addition of new nodes and edges to a graph to 'watch it grow' is to something Mathematica is not suited to by default. However this type of animation really helps convey the emergence ...
8
votes
3answers
297 views

Pairwise distances of points and classification using GraphDistanceMatrix

The challenge Given $n$ points in $\mathbf{R}^3$ and a cutoff distance, $d$, I would like to determine all pairs of points that are separated by less than the given cutoff distance, $d$, and all ...
8
votes
4answers
335 views

Can I stop edges in graphs from drawing on top of the vertices?

Consider the following testadj = RandomVariate[BernoulliDistribution[0.15], {50, 50}]; AdjacencyGraph[testadj, VertexSize -> Large] The nodes are almost ...
8
votes
2answers
285 views

Organise a graph's vertices into levels

I would like to organise a graph's vertices in levels. Consider ...
8
votes
2answers
365 views

Efficient setting of properties of multiple vertices in Graph

The functions SetProperty and PropertyValue can only set a single property of a single vertex, as far as I know. How do I set a ...
8
votes
2answers
378 views

Graphing a network with state transition flows (of varying size)

In one of Stephen Wolfram's recent blog posts (http://blog.stephenwolfram.com/2013/04/data-science-of-the-facebook-world/#more-5350) he provides the network plot below. The size of the arrows that ...
8
votes
3answers
448 views

Mathematica 10 Graph issue

fixed in 10.0.2 Please try to evaluate this code in Mathematica 10. ...
8
votes
2answers
351 views

How do I convert this Nicomachus's Triangle to one with edges?

I want to put edges on this Nicomachus's Triangle r = 7; t = Table[2^(n - k) 3^k, {n, 0, r}, {k, 0, n}]; ColumnForm[t, Center] Is there an easy way to do this? ...
8
votes
2answers
272 views

Cases[data,Colon[key,_]] vs. Cases[data,key:_] toward XPath, XQuery

Exploring methods to index and search tree-structured key:value pairs via named-entity index (key paths) as opposed to Position-based indexing. Using Rule as ...
8
votes
2answers
2k views

How to find the Shortest Path, visiting ALL vertices, without coming back to the start (Hamiltonian Path, minimum distance)

A car has to pick up each person and take them to their destination. I am trying to find the shortest tour that will do this. How can I find the shortest path between any s and t.... visiting all ...
8
votes
3answers
280 views

Preserving labels when using graph functions

I am finding that some functions that accept a graph and return a transformed graph lose all the vertex and edge labels of the graph being transformed. For example, when I define a graph like this: ...
8
votes
1answer
172 views

Using GraphHighlight interactively

I want to build a small GUI, where the user can select either a single edge or a single node of a graph. I got to this point: ...
8
votes
1answer
296 views

How can I sequentially apply different graph embeddings?

Imagine I have some graph G, and I perform a graph embedding using a command like: ...
8
votes
3answers
450 views

TreePlot with centered vertexes

I want to draw a tree plot for Euler totient function for this question like the following: I generate the EulerPhi for first 20 numbers into a list: ...
8
votes
2answers
530 views

HighlightGraph with different styles

I want to highlight two different directed paths on a graph with two different style. I am using the following two code snippets: ...
8
votes
1answer
184 views

Vertex merging in graph?

Given a Graph such as the one produced with the following code ...
8
votes
2answers
897 views
8
votes
1answer
811 views

How to add vertex/edge labels to existing graph

If I have already created a graph using Graph. Later, I want to add to the graph some vertex and/or edge labels, how can I do that? Thank you.
8
votes
2answers
175 views

Relaxation of Mass-Spring System with Pinned Masses

Problem Assume that four masses are connected to each other by springs while two of them are pinned down at their initial positions. Find the position of masses when system is at its minimum ...
8
votes
2answers
176 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: ...
8
votes
1answer
511 views

Why does SocialMediaData return such a small FollowerNetwork?

I have hooked up my Twitter account to Mathematica and I have 1468 followers myfollowers = Length[SocialMediaData["Twitter", "Followers"]] 1468 I wondered what ...
8
votes
2answers
316 views

Finding All Chordless Simple Cycles In A Graph

I am doing a research on networks which consists of polygons with different number of sides. I am trying to find all simple cycles in a network which are chordless. As an example, consider the ...
8
votes
0answers
77 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 ...
7
votes
5answers
417 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 ...
7
votes
2answers
470 views

Convert Graph to Graphics

In Mathematica 9, a graph is returned as an object with head Graph: In[8]:= CompleteGraph[8] // Head Out[8]= Graph ...
7
votes
5answers
585 views

Building graph based on the cities connection?

I built a Graph based on the permutations of city's connections from : ...
7
votes
3answers
2k views

Travelling salesman with start and end points for 30 points

I am doing a route optimisation for delivery vehicles and failing dismally. Please see problem statement below. My current solution uses FindShortestTour, but this does not have defined start and end ...
7
votes
3answers
289 views

Converting Mesh in Density Plots to a Graph

Consider the following line of code: ...
7
votes
3answers
441 views

I can't understand FindShortest Tour

I can't understand the function FindShortestTour because of the result: FindShortestTour[{ {0, 1}, {5, 1}, {2, 1}, {10, 1}}] ...
7
votes
3answers
675 views

Visualizing the output of a Voronoi diagram computation

I need to plot a graph (to be specific: Fortune Algorithm output) with given vertex coordinates and a few unconnected vertices. I am thinking of using Mathematica for that. ...
7
votes
3answers
367 views

How to remove all dead ends from a undirected graph?

so what I want to do is take an undirected graph, and remove all the "dead ends" (that is, vertices that are attached to only one other vertex), but do it in such a way that it does it until reaches ...
7
votes
2answers
1k views

Is it possible to export a graph as graphic to Excel?

It is straightforward to export lists to Excel with Export. Can I export a graphic image, too? This does not work: ...
7
votes
2answers
702 views

Controlling TreePlot (and GraphPlot) layout issue

A continuing battle with Mathematica involves graphics heavy with text labels. For example, the following expression renders so that the "Lifecycle properties..." ...
7
votes
3answers
302 views

Different colors for nodes in tree plot

I have some list of numbers which I am plotting using TreePlot. This is the code: ...
7
votes
3answers
751 views

Random Geometric Graphs

I'm trying to implement an application which uses random geometric graphs in Mathematica, but it seems Mathematica lacks the functionality. I need the following functionalities: Generate a set of ...
7
votes
2answers
492 views

Can I put tooltips in a Graph?

This doesn't work: Is there a way to do this? My real goal is to identify the second links in the graph below, which shows the results of a webcrawl (using this code). I'm open to another ...
7
votes
1answer
149 views

Replacing graph nodes with matrices

I would like to label a graph with matrices. Suppose the graph is simple: And I have an array mats that contains the labels for vertices 1,2,3,4 (these are just random 0-1 matrices; ignore the ...
7
votes
2answers
290 views

Is there a bug in FindClique?

If h is a graph, FindClique[g, {n}] should return a clique on exactly $n$ vertices if one exists in ...
7
votes
4answers
3k views

How to generate and draw simple bipartite graphs?

A bipartite graph is a graph whose vertices can be divided into two disjoint sets. Given two lists: {1, 2, 3} and {x, y, z}, ...
7
votes
2answers
364 views

Colorize and the Four-Color Theorem

We can write: MorphologicalComponents[image] // Colorize To assign a random set of colors to each component in some image. The example used for reference by ...
7
votes
2answers
530 views

Edge problems in a directed graph

I want to create the following two graphs. So far I tried the following Code ...
7
votes
2answers
789 views

Coloring edges in GraphPlot

I'm a little stuck with graph drawing part of my research — I can't use the Graph function for plotting my graphs, because my graph is a multi-graph. ...
7
votes
4answers
225 views

Automatically convert pairs of directed edges to an undirected edge?

I have a directed graph, which for some pairs of vertices, has a directed edge between them in each direction. I would like to replace such pairs of directed edges between the same vertices but in ...
7
votes
1answer
184 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 ...
7
votes
3answers
331 views

Nested list to graph

The following nested list can be regarded as a representation of a (tree) graph: ...
7
votes
2answers
534 views

How to add new nodes to an existing graph with fixed (coordinates) nodes?

I'm ultimately trying to create a directed graph with some of the nodes in fixed positions and the other nodes placed around them in "acceptable" positions. It's better if I ask the question by ...
7
votes
1answer
1k views

Mathematica: Label specific vertices in GraphPlot

How can I label particular vertices in GraphPlot? And have the arrows space out accordingly, for the width of the label? I have Mathematica 7, but I think this question applies to all versions. ...
7
votes
2answers
113 views

How can I recover a graph from a graphical output in a notebook after resetting the kernel?

I have an old Mathematica notebook with an output for a graph structure $G$ I would like to recover. However, the routine for building up the graph is stochastic, so I can't simply rerun the code. ...