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 generate random directed connected graph?

How to generate random directed connected graph? I need to create graph which will pass: ConnectedGraphQ[^]
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1answer
347 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. ...
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3answers
290 views

Centrality measures for single nodes

I am producing a graph, generated by a list of adjacent nodes. (The list looks like {1 ->583, 1->2977, 2->14, 4->1293, 5->221, ...}. Each node of my ...
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1answer
307 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 ...
5
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1answer
126 views

Keeping vertexcoordinates after adding a new vertex

I want to add a new vertex to a graph, with fixed VertexCoordinates but when I use VertexAdd, the new graph does not have the VertexCoordinates of the previous one. ...
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3answers
213 views
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2answers
301 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 ...
5
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1answer
415 views

How can I draw a polygon from a set of angles?

In recreational mathematics, polytans are polygons formed by edge-connecting isosceles right triangles. Order-n polytans are those constructed from n such triangles. My question is this: Given a ...
5
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2answers
260 views

Is there something akin to “SubgraphIsomorphismQ” in Mathematica 9?

Provided two unlabeled graphs, $G$ and $H$, I would like to test where $H$ is a subgraph of $G$. In other words, I'd like to test whether we can prune some fixed number of vertices or edges from $G$ ...
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2answers
180 views

Is there something wrong with VertexConnectivity

As I noticed in the documentation VertexConnectivity is defined as the following The vertex connectivity of a graph $g$ is the smallest number of vertices whose ...
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3answers
238 views

Export Graph to PDF

I know that I exported Graphs to PDFs before but it doesn't seem to work any more. I tried K5 = GraphData[{"Complete", 5}] Export["K5.PDF", K5] And I get a PDF ...
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2answers
322 views

Merging (combining) tables of graph relationships (2-mode to 1-mode network)

I have some data of corporate board members in Australia in excel format here (Dropbox public link). It is the data behind this graph. The first worksheet is of all the vertexes (directors and ...
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2answers
491 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. ...
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3answers
217 views

Fast code to generate large random graph with fixed degree sequence

I'm trying to create a function so to generate large random graph with a fixed degree sequence $\{v_1,v_2,\dots,v_N\}$, where $N$ is the number of vertices in the graph. The Mathematica function that ...
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1answer
396 views

All possible topological orderings of a graph

TopologicalSort[] returns one of many unique orderings. From wikipedia: if a topological sort does not form a Hamiltonian path, the DAG will have two or ...
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2answers
263 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 ...
5
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2answers
208 views

Graph does not evaluate some options when not displayed

How can I force Graph to evaluate all its options without actually displaying the graph itself? Evaluating the following code ignores the ...
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1answer
343 views

Accessing the graph Thinning produces without losing all the edges' lengths/slopes

This is a follow up to the OCR question I had earlier. What I want to do is to use Thinning to create "skeletons" of images of characters and then compare their shapes, utilizing such properties ...
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1answer
275 views

How to determine edgeweights from width of skeleton using MorphologicalGraph (or workaround)?

Background I'm trying to create a workaround for what seems to be a bug in MMA's graph functions related to edge weights: SO: How to Label Graph Edges with their weights According to MMA's ...
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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
216 views

Processing and storing a graph with a large number of vertices s.t. k-hop neighborhoods are efficiently retrievable

I have an unweighted, undirected graph $G$ with $(v_1, ..., v_N) \in V$ vertices, where each vertex in the lattice represents a string of some length ($\leq 200$ characters), and I need to construct ...
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1answer
66 views

Setting PropertyValue for VertexWeight is not persistent

g = CompleteGraph[8, VertexSize -> Medium]; PropertyValue[{g, VertexList[g][[1]]}, VertexWeight] = 10; PropertyValue[g, VertexWeight] ...
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0answers
225 views

How to compute the genus of a Graph?

What's the simplest way to compute the genus of a graph using Mathematica? I have looked for a Genus function (even in the ...
5
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0answers
69 views

Graph relationships between functions and variables [duplicate]

Possible Duplicate: Has anyone written any function to automatically build a dependency graph of an arbitrary Mathematica function? I need to make sense out of a huge notebook (17Kloc) ...
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2answers
219 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 ...
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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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212 views

Efficiently determining the largest minimum cost to travel from a fixed source to an arbitrary sink in a weighted graph

Let $v_i$ be a vertex in a graph $G$ with vertices $(v_1,...,v_N) \in V$ and edges $(e_1,...,e_M) \in E$ with associated weights $(w_1,...,w_M)$. Let $v_s \in V$ be specified vertex in the graph. In ...
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2answers
205 views
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473 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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2answers
146 views

HighlightGraph with style

In this picture you see a graph. The shortest path between vertex 5 and vertex 3 is highlighted in red. Instead I want blue highlighted edges of thickness 10. ...
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2answers
978 views

How do I plot a solution of a differential equation?

I am having trouble generating a plot for a solution to my differential equations. I always end up with just blank axes. ...
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3answers
430 views

Graph generation given number of edges and nodes

I was wondering if it is possible to have Mathematica generate all graphs with a given number of edges and nodes (and possibly restricting the adjacencies) and draw them I know that there are some ...
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2answers
184 views

Odd behavior of GridGraph and DirectedEdges

For some reason the option DirectedEdges->True, albeit working internally with grid graph, does not appear in the visualisation for 1D and 2D graphs. It also ...
4
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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: ...
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2answers
712 views

Finding face vertices from the face adjacency graph

I have a question about face adjacency graphs. Suppose that I have an adjacency matrix ...
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1answer
326 views

Get the neighboring vertices and incident edges from a vertex in a graph

I need to get the neighboring vertices and incident edges from a vertex in a graph. I assume NeighborhoodVertices can be used for the former. Anything better? Or ...
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3answers
404 views

Place graph vertex labels in circles

Consider the following code: ...
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2answers
143 views

Nested list to graph

The following nested list can be regarded as a representation of a (tree) graph: ...
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1answer
70 views

How to impose control over vertex-to-vertex Graph edges?

I’m working on a Markov Chain and hope there is a way to impose control over how Mathematica places edges to connect vertices in a Graph. My Markov Chain currently consists of 4 vertices with 2 of the ...
4
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1answer
129 views

Analysis of Facebook group

I am the admin of a Facebook group for our year at university and wanted to graph the members of the group like you can with your own friends so we can find the isolated people and get rid of them (as ...
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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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 ...
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1answer
597 views

Creating a weighted, directed graph from ordered triples

I have a relatively large set of data that I am trying to turn into a weighted, directed graph. The data concerns the inflow of migrants based on country of origin. I currently have three columns of ...
4
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1answer
199 views

Counting the size of the minimum cut produced by MinCut of GraphUtilities`

I want to use the MinCut function of the GraphUtilities` package to find minimum cuts for a few graphs. I'm completely new to ...
4
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1answer
150 views

HITS centrality

I want the centrality measure of a particular vertex in my graph, and for Closeness, Betweenness and Degree centralities I have been using : ...
4
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1answer
81 views

Katz Centrality [closed]

I want to calculate the Katz Centrality of large graphs. The Mathematica command to do that is KatzCentrality[g, $\alpha$] and it is also fast. However I realized that there is a mismatch between ...
4
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1answer
117 views

Compatibility issues for Combinatorica package

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

LayeredGraphPlot: two instances of the same label

What I'd like to do is to have the same label more than once in the plot. I.e. I do not want the edges to direct toward the first instance of that label! For example: ...
4
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1answer
846 views

When do I use Mathematica, when do I use Gephi, and how do I use them together?

Mathematica has great operations for analyzing graphs but when the graphs are a bit bigger, Gephi seems to be more efficient (at least on my computer) at drawing and analyzing, i.e. visualizing the ...
4
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1answer
48 views