# graph-mpd: Maximal prime subgraph decomposition In gRbase: A Package for Graphical Modelling in R

 graph-mpd R Documentation

## Maximal prime subgraph decomposition

### Description

Finding a junction tree representation of the MPD (maximal prime subgraph decomposition) of an undirected graph The maximal prime subgraph decomposition of a graph is the smallest subgraphs into which the graph can be decomposed.

### Usage

```mpd(object, tobject = minimal_triang(object), details = 0)

## Default S3 method:
mpd(object, tobject = triangulate(object), details = 0)

mpdMAT(amat, tamat = minimal_triangMAT(amat), details = 0)
```

### Arguments

 `object` An undirected graph; a graphNEL object, an igraph or an adjacency matrix. `tobject` Any minimal triangulation of object; a graphNEL object, an igraph or an adjacency matrix. `details` The amount of details to be printed. `amat` An undirected graph; a symmetric adjacency matrix `tamat` Any minimal triangulation of object; a symmetric adjacency matrix

### Value

A list with components "nodes", "cliques", "separators", "parents", "children", "nLevels". The component "cliques" defines the subgraphs.

### Author(s)

Clive Bowsher C.Bowsher@statslab.cam.ac.uk with modifications by Søren Højsgaard, sorenh@math.aau.dk

### References

Kristian G. Olesen and Anders L. Madsen (2002): Maximal Prime Subgraph Decomposition of Bayesian Networks. IEEE TRANSACTIONS ON SYSTEMS, MAN AND CYBERNETICS, PART B: CYBERNETICS, VOL. 32, NO. 1, FEBRUARY 2002

`mcs`, `mcsMAT`, `minimal_triang`, `minimal_triangMAT`, `rip`, `ripMAT`, `triangulate`, `triangulateMAT`

### Examples

```
## Maximal prime subgraph decomposition - a graphNEL object
g1 <- ug(~ a:b + b:c + c:d + d:e + e:f + a:f + b:e)
if (interactive()) plot(g1)
x <- mpd(g1)

## Maximal prime subgraph decomposition - an adjacency matrix
g1m <- ug(~ a:b + b:c + c:d + d:e + e:f + a:f + b:e, result="matrix")
if (interactive()) plot(as(g1m, "graphNEL"))
x <- mpdMAT(g1m)

```

gRbase documentation built on April 2, 2022, 5:06 p.m.