gRain (version 0.3.0)

grash-operations: Operations on undirected and directed acyclic graphs.

Description

Make operations on undirected and directed acyclic graphs.

Usage

moralize(dag)
mcs(ug,amat=as.adjmat(ug), vn=colnames(amat), root=NULL, index=FALSE)
triangulate(ug,method="standard", nLevels, matrix=FALSE)
ripOrder(ug,root=NULL,nLevels=NULL)
jTree(ug, method="standard", vn=nodes(ug),nLevels, control=list())

Arguments

dag

A directed graph (of class "dagsh")

ug

An undirected graph (of class "ugsh")

method

The triangulation method, "standard" is a C implementation of a minimum clique weight heuristic, "mcwh" is a Fortran implementation of the same (kindly provided by Peter Green) and "R" is a correspondi

matrix

Should the triangulated graph be returned as an adjacency matrix

amat

The graph represented as an adjancecy matrix

vn

The node names as they appear in the adjancecy matrix

root

Variables which must be in the first clique in the rip-ordering

nLevels

Number of levels of the nodes in the graph

index

If TRUE, then a permutation is returned

control

Currently not used

...

Currently not used.

Value

• moralize and triangulate returns objects of class "graphsh". mcs returns a vector or NULL. ripOrder returns a list with cliques, separators etc.

Details

The jTree (for "junction tree") is just a wrapper for a call of triangulate followed by a call of ripOrder.

See Also

newugsh, newug, newdagsh, newdag

Examples

## Undirected graphs
##
ug <- newug(~me+ve,~me+al,~ve+al,~al+an,~al+st,~an+st)
edges(ug)
nodes(ug)
mcs(ug)
ripOrder(ug)

## Directed graphs
##
dag <- newdag(~me+ve,~me+al,~ve+al,~al+an,~al+st,~an+st)
edges(dag)
nodes(dag)
moralize(dag)