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
122 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
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3answers
881 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
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3answers
355 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
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0answers
152 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
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3answers
718 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
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1answer
125 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
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1answer
78 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
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2answers
418 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
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2answers
254 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
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3answers
484 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
143 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
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2answers
123 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
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3answers
315 views

Flow in pipeline graph

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

Compatibility issues for Combinatorica package

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

Organise a graph's vertices into levels

I would like to organise a graph's vertices in levels. Consider ...
3
votes
3answers
197 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
205 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
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1answer
130 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
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2answers
406 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
233 views
0
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1answer
96 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
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3answers
170 views
2
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1answer
111 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
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2answers
924 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
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2answers
223 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
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1answer
219 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
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1answer
159 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
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2answers
425 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
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1answer
98 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
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1answer
129 views
3
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1answer
242 views

Vertex Labeling Problem in a Graph

I am using following codes to create a graph. ...
10
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1answer
628 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 ...
6
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1answer
77 views

Setting PropertyValue for VertexWeight is not persistent

g = CompleteGraph[8, VertexSize -> Medium]; PropertyValue[{g, VertexList[g][[1]]}, VertexWeight] = 10; PropertyValue[g, VertexWeight] ...
1
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1answer
92 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 ...
5
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1answer
656 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 ...
9
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1answer
109 views

FindHamiltonianCycle is not invariant to edge permutation

Found this bug-like behaviour today: if the order of edges is changed so that VertexList does not return the vertices in canonical order, ...
3
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1answer
54 views

Problems with PropertyValue when Graph's vertices are Lists

I create a Graph which vertices are lists (points in n-dimensional space) ...
3
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1answer
176 views

How can I highlight and individually color the connected components of a graph?

I have a graph G, and I wish to individually highlight and color the different connected components of a graph. It is simple enough to do this for one component: ...
1
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1answer
181 views

Do any users know of methods to capture Twitter feeds and subject them to analysis? [duplicate]

I would like to use the output of about 300 Twitter sources and would probably collect 30 minutes of tweets at a time and subject each collection to analysis; ideally this process would be automatic ...
1
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2answers
144 views

Separating disconnected graph objects without losing vertex coordinate assignments

Say I have a graph Gtest, which has multiple disconnected components. I found that I can isolate individual components while retaining vertex coordinate ...
0
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1answer
35 views

Parsing output from FindHamiltonianCycle to recover an ordered list of vertex positions for a discovered path

After applying FindHamiltonianCycle to a graph, one generates output that looks like the following: ...
1
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2answers
646 views

How do I divide the columns of a matrix by the sum of its elements?

I am trying to create a transition matrix for a network. In order to do this, I need to sum down the column (the out degree), and then divide the column by the out degree in order to normalize it. ...
5
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1answer
160 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. ...
12
votes
4answers
1k views

Finding elementary cycles of (directed) graphs

I need to enumerate all the simple cycles (i.e. elementary cycles where no vertex is repeated other than the starting) of a graph which has both directed and undirected edges, where we can treat the ...
6
votes
2answers
359 views

Sierpinski carpet with GraphData

Is this graph in the list among the so-called "standard" structures used in GraphData? However, I have not found, yet, anything like "Carpet" or "Sponge" in the ...
4
votes
4answers
521 views

Graph Creation in Mathematica: TSP

I'm trying to create the following graph in Mathematica Where do I start? I'm specifically trying to make a graph so that I can use it in TravelingSalesman[g], ...
2
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3answers
193 views

Graph with $\{a,b\}$ as Vertex Instead of Number

I'm trying to create a graph which has $\{a,b\}$ as labels: ...