# Tagged Questions

Questions on the use of Mathematica in combinatorics, including the Combinatorica add-on package.

2answers
112 views

### Checking connectedness of a graph

I am trying to use the Combinatorica package in a Mathematica version 8 in the following code: ...
1answer
388 views

### Better way to get Fisher Exact?

I want to perform a Pearson's $\chi^2$ test to analyse contingency tables; but because I have small numbers, it is recommended to perform instead what is called a Fisher's Exact Test. This requires ...
3answers
202 views

### Permutation count for sets with multiplicities

I am able to do a permutation counr for the set {a, a, b} which gives me 3 groups. I am happy with that result. However, if the set is ...
4answers
492 views

### How to enumerate all possible binary associations?

Suppose I have a list of symbols like: {a,b,c,d} I would like to enumerate all possible binary associations (combining symbols and/or sublists pairwise): ...
1answer
838 views

### How to implement Kemeny-Young method? (rank aggregation problem)

Prehistory I am trying to make some statistical analysis of some experimental data, arises from measurements made ​​on an ordinal scale. I faced with the problem of rank aggregation: to get from ...
1answer
269 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: ...
1answer
200 views

### How can I find the derivative of a combinatorial expression? [closed]

I want to differentiate the following equation: n = (nchoosek)*p*(1 - p)^(n - k) After differentiating my result is: ...
0answers
77 views

### The number of real values assumed by combinations of complex roots of a decic

Define complex conjugate as the pair of complex numbers $a+bi,a-bi$. Assume you have 5 such pairs and they are the 10 roots $x_i$ of a 10th-deg equation with integer coefficients. In general, how many ...
1answer
292 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 ...
4answers
411 views

### Equivalent Nested Loop Structure

Consider the following examples: ...
0answers
58 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 ...
2answers
173 views

0answers
362 views

### Get path to end nodes in directed (partially cyclic) graph

I have a large directed graph containing small loops. I would like to extract all paths to all end nodes (no VertexOutComponent) with a given path length $n$. I ...
1answer
378 views

3answers
1k 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: ...
5answers
834 views

### Getting number of binary digits combinations without “forbidden” patterns

I need to get the number of all combinations of binary digits in an 8-digit binary number, but not including those that follow some "forbidden" patterns like these: ...