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
95 views

Reflecting the Polya-Aeppli distribution

How would I go about reflecting the Polya-Aeppli distribution in Mathematica about a y-axis (switching left and right) while keeping the command. The distribution will not allow negative parameters ...
6
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1answer
223 views

How to visualize the structure of this dynamic programming code

I am studying Mr. Wizard's answer to this question which tries to identify elementary circles in a graph. That answer uses dynamic programming technique to simplify the code. The underlying guideline ...
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3answers
100 views

Deleting Vertices in GridGraph

Take a simple GridGraph: g = GridGraph[{3, 3}, VertexLabels -> "Name", ImageSize -> 150, ImagePadding -> 10] I am ...
2
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1answer
193 views

Nicely illustrating the evolution and end-state of a discrete-time Markov chain

I'm simulating a discrete time Markov process on a finite state space corresponding to a linear interval $(x_1, x_2, ..., x_N) \in X$, where each time step $t_i$ involves updating the state of some ...
5
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1answer
308 views

How to display each step of an A star algorithm?

I wrote a pathfinding program: A*, which is an extension of Dijkstra. I want to see the result of each step at a time. Which function should I use? The main program is the notebook Astar, which is ...
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1answer
90 views

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

I have a list of edges defined based on vertices like this: ...
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2answers
158 views

Visualize difference between members of the list

I want to visualize the difference between members of a set: set = {20, 36, 70, 96, 152, 301} This way I get the diffs: ...
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1answer
53 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 ...
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1answer
101 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 ...
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2answers
236 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 ...
3
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2answers
148 views

Manually adjust graph vertex location by dragging?

Sometimes I have a graph and I want to make tweaks to the vertex locations. Is there any way to manually adjust graph vertex location by dragging? If I double click to edit, I can move around the ...
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1answer
119 views

Vertex labels versus vertex names in VertexRenderingFunction

The VertexRenderingFunction seems to only use names, not labels. For example: ...
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1answer
89 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 ...
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2answers
161 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: ...
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1answer
90 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 ...
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1answer
134 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
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1answer
123 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 ...
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1answer
156 views

Mean path length of randomly generated graphs

I am looking to find the the average path length of 1000 random graphs with the following degree distribution, a few of the vertex degrees are included below ...
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0answers
54 views

GraphHighlightStyle with multiple datasets

I am trying to highlight several subgraphs of a graph using the following command: ...
5
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1answer
183 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: ...
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1answer
96 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: ...
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0answers
91 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 ...
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3answers
229 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 ...
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0answers
53 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
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1answer
118 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 ...
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1answer
61 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. ...
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1answer
149 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 ...
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2answers
212 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 ...
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0answers
87 views

Any useful operations on LinkedIn data?

I have connected to LinkedIn using SocialMediaData, but the information seems to be limited to my connections and their IDs. How is this interesting? Is there a way to load a network using the ...
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1answer
95 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 ...
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2answers
108 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: ...
4
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1answer
118 views

Compatibility issues for Combinatorica package

I am trying to use the Combinatorica package in a Mathematica version 9 in the following code : ...
6
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3answers
239 views

Flow in pipeline graph

I have pipeline directed graph which has one source and several sinks ...
8
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2answers
206 views

Organise a graph's vertices into levels

I would like to organise a graph's vertices in levels. Consider ...
3
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3answers
152 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
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4answers
176 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 ...
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2answers
142 views

Total weight of a graph

I need to find the total weight of an WeightedAdjacencyGraph. I have a graph in that form ...
4
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3answers
480 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 ...
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3answers
272 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 ...
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1answer
106 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: ...
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2answers
233 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
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1answer
160 views

Merging Vertices of a Graph and adding up the edges weights

I have a Weighted Graph of g which looks like this. ...
0
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1answer
56 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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3answers
126 views

Different Vertex Styling in a Graph

We can have this Graph: ...
2
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1answer
103 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: ...
3
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0answers
208 views

How to compute the Lovász number for the given graph in Mathematica?

Here is a graph whose adjacency matrix is ...
0
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1answer
88 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
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1answer
152 views

Vertex Labeling Problem in a Graph

I am using following codes to create a graph. ...
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1answer
89 views

Is there a TwoColoring function of Graph object?

The following code shows the GraphUtilities package makes a problem for Graph object. I want to use a ...
10
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1answer
450 views

Roads network visualization by thickness and color intensity by population from GIS files

We can have road networks of the countries in GIS shape file.For exmple from here. Normally traffic flows are proportionate to populations of the cities. I wonder how we can have the same in ...