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

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0
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1answer
127 views

GraphPlot3D: How to plot undirected graph with a list of edges?

I have a list of edges defined based on vertices like this: ...
0
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1answer
67 views

Subgraph, HighlightGraph not acting as expected

I'm trying to create a simple graph from a matrix and then highlight a particular subgraph. My code (simplified from a bigger task) is as follows. I keep getting the "Subgraph::graph: A graph object ...
0
votes
1answer
142 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 ...
2
votes
2answers
300 views

random geometric graph generation problem

I'm new to Mathematica. I'm trying to generate a random geometric graph in which to have a secure link between any two arbitrary nodes they should share a common key in their key rings (have assigned ...
22
votes
2answers
3k views

How to play with Facebook data inside Mathematica?

I saw this post from Wolfram here and I would like to know how to import facebook data into Mathematica.
3
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2answers
165 views

How to apply GraphLayout to parts of a graph?

I'm trying to sketch polymers. Here is how I do it for the monomer: ...
1
vote
1answer
106 views

GraphPlot with black edges no rendering function

Is there any way to make the edges of a GraphPlot black without tediously writing out a long "EdgeRenderingFunction"? I guess you could ask the same kind of question about vertex labeling. For ...
3
votes
1answer
284 views

Generating a graph object where vertices are pixel coordinates and edges represent two pixels being in the same Moore neighborhood

I have a list of integer pixel positions, pts, and I wish to create one or more graph objects where vertices at these pixel positions share an edge if they are ...
3
votes
1answer
92 views

Is there really a bug in the following code, taken from the reference documentation for PetersenGraph?

PetersenGraph[5, 2, EdgeLabels -> {8 \[UndirectedEdge] 9 -> "hello"}] appears to evaluate perfectly, as expected, but in my version 9.0.1.0, the option ...
2
votes
1answer
186 views

GraphPlot labels overlapping

If I plot the following graph with an EdgeRenderingFunction, the position of both the labels are at dead center, and with a large graph I have the labels completely ...
15
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3answers
231 views

What is the most convenient way to change options for Graph[] objects?

What is the most convenient way to change options such as VertexLabels in existing Graph objects? (Version 7 users note: ...
13
votes
4answers
437 views

How to recompute the layout of a Graph?

I asked a question about changing Graph properties in a similar way to how Show can change ...
2
votes
3answers
399 views

GraphPlot only working when I evaluate twice

I have some code that builds a graph and some vertex coordinates, but when I evaluate it I get a message that the list of coordinates is not valid and the graph is not valid and it shows the output as ...
2
votes
1answer
163 views

Finding a Moore neighborhood connected path of bright pixels along the contour of a text character

I have a simple image, for example a blowup of a Times New Roman character like 'R' saved as a PNG. I then perform the following operations to extract a minimum representation of the contour lines ...
4
votes
1answer
146 views

Dijkstra without Combinatorica

There is some overlap between Combinatorica and the Graph related framework but there are also various elements missing. As far as I can see there is no 'Dijkstra' method or algorithm in Mathematica ...
1
vote
0answers
61 views

GraphHighlightStyle with multiple datasets

I am trying to highlight several subgraphs of a graph using the following command: ...
5
votes
1answer
197 views

Shortest polygonal path

I'd like to find the shortest distance between some points (every point must be visited), such as between these 3 points: ...
0
votes
1answer
111 views

Connected components of a graph

I am trying to find the number of connected components of numerous named graphs within Combinatorica. The obvious answer seems to be: ...
4
votes
3answers
726 views

Minimum spanning Tree from a weighted adjacency graph

Note: Cross-posted at http://community.wolfram.com/groups/-/m/t/137658?p_p_auth=8QnKtT9I I have a really big graph, 40x40. Here is my code ...
3
votes
3answers
302 views

Generating a graph where vertices correspond to points in an integer lattice and edges connect points less than a threshold distance apart

I'd like to automatically generate a graph where vertices correspond to (and have the coordinates of) points in an $A \times B$ integer lattice, and a graph is generated by connected vertices within a ...
1
vote
0answers
132 views

Tools for finding minimal or almost-minimal graph vertex colorations in Mathematica v9?

I'm looking to compute minimum vertex colorations (s.t. no two vertices of the same color share an edge: http://en.wikipedia.org/wiki/Graph_coloring) for graphs in Mathematica v9 with potentially up ...
4
votes
3answers
621 views

How to find all graph isomorphisms in FindGraphIsomorphism

I found the second definition of the function FindGraphIsomorphism not working. Here's the definition Mathematica 8 gives: ...
2
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0answers
55 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 ...
9
votes
1answer
122 views

How to get control over DepthFirstScan?

Is there a way to conditionally take control the flow during a depth-first scan against a TreeGraph? I have a tree graph whose nodes are constructed as object, and there's a method ...
1
vote
1answer
72 views

Assigning Variables for Degree Distribution [closed]

So my code is divided into 3 different sections: 1) Calculating clustering coefficient, 2) Extracting degree distribution 3) Using the degree distribution to get the mean of 1000 networks. ...
1
vote
2answers
347 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 ...
6
votes
2answers
238 views

How do I reorder vertices in a graph?

I have a directed acyclic graph $g$, and I'd like to re-order the vertices in this graph object such that when I call VertexList[myGraph] the vertices appear in ...
9
votes
3answers
412 views

Remove redundant dependencies from a directed acyclic graph

Given a directed acyclic graph, I want to remove all the edges $v_i \rightarrow v_j$ if $v_j$ is reachable from $v_i$ by some other path. Given the rich set of graph algorithms in Mathematica, what is ...
1
vote
1answer
127 views

Gradually coloring edges in terms of their vertices colors

In order to color Edges in a Graph after applying a function such as VertexDegree I did the ...
4
votes
2answers
118 views

BezierCurve in EdgeShapeFunction fails when used on multiedges graph

I would like to create a network graph with curved edges. To do this, I wrote this function: ...
6
votes
3answers
282 views

Flow in pipeline graph

I have pipeline directed graph which has one source and several sinks ...
4
votes
1answer
169 views

Compatibility issues for Combinatorica package

I am trying to use the Combinatorica package in a Mathematica version 9 in the following code : ...
8
votes
2answers
244 views

Organise a graph's vertices into levels

I would like to organise a graph's vertices in levels. Consider ...
3
votes
3answers
180 views

Product of edge weights in path

I need to calculate the product of graph edge weights on the path taking into account edge direction. I.e. for graph ...
6
votes
4answers
191 views

Draw graph wherein vertices are ArrayPlots

I need to place ArrayPlots in the vertices of graph. i.e. in graph Graph[{1->2, 2->3, 3->1}] I have to replace vertex 1 with ArrayPlots[{{0,0,1}}] and ...
1
vote
1answer
123 views

Problem with GlobalClusteringCoefficient

I have a simple problem, I would like to measure the global clustering coefficient for a random graph. Here is my code: ...
1
vote
2answers
322 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: ...
3
votes
1answer
189 views
0
votes
1answer
72 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 ...
1
vote
3answers
154 views
2
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1answer
110 views

Distances of locations in the matrix form

I want to have the distances of the cities in the matrix form.How can I have it for example for the cities like followings that also includes the distance of the city from itself which is zero: ...
4
votes
2answers
856 views

Finding face vertices from the face adjacency graph

I have a question about face adjacency graphs. Suppose that I have an adjacency matrix ...
3
votes
0answers
225 views
3
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2answers
205 views

How can I construct “better” block graphs?

A graph is a block graph if it can be constructed from an undirected tree by replacing each edge with a clique. My method of generating "random" block graphs is as follows. The parameters are the ...
7
votes
1answer
194 views

How to scale edge length and keep layout of edge-weighted Graph?

I love using Graph as structure to store and visualize my data in Mathematica. Consider the following simple example for creating a ...
1
vote
1answer
151 views

Find size of vertex image relative to the graph coordinate system

I am trying to define a graph using my own VertexShapeFunction with an ActionMenu button being the vertex and a custom ...
5
votes
2answers
334 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 ...
1
vote
1answer
96 views

FindEdgeCut with weighted graphs

If I want to find a minimum cut between two nodes in a weighted graph, I would use FindEdgeCut as follows: ...
0
votes
1answer
114 views

How can I replace UndirectedEdges to pairs of bi-directional DirectedEdge in a Graph?

How can I have pair of edges between nodes in this kind of graphs? ...
3
votes
1answer
192 views

Vertex Labeling Problem in a Graph

I am using following codes to create a graph. ...