adjacencyList-class: Class "adjacencyList"
In ClausDethlefsen/giRaph: The giRaph package for graph representation in R

Description Objects from the Class Slots Extends Methods Warning Note Author(s) See Also

A class for adjacency list representation of multi-graphs

Objects can be created by calls of the form new("adjacencyList",id,pa,ne).

.Data:: Object of class "list"; each element represents a vertex and is in turn a list of (at most) three elements, namely pa, ne and ch storing, respectively, the numeric identifiers of parents, neighbours and children

Class "list", from data part. Class "vector", by class "list".

initialize: signature(.Object = "adjacencyList"): constructs an adjacency list representation of a multi-graph from a vertex set id, a list pa of parent numeric identifiers, a list ch of children numeric identifiers, and a list ne of neighbour numeric identifiers
show: signature(object = "adjacencyList"): displays an adjacency list representation
names: signature(x = "adjacencyList"): gets the character vertex identifiers of an adjacency list
names<-: signature(x = "adjacencyList"): sets the character vertex identifiers of an adjacency list
card: signature(object = "adjacencyList"): returns the number of vertices and the total number of edge occurrences in an adjacency list
isEmpty: signature(object = "adjacencyList"): an adjacency list is empty if it has no entries
isPresent: signature(el = "undirectedEdge", ou = "adjacencyList"): tells whether an undirected edge occurs in the multi-graph represented by an adjacency list
isPresent: signature(el = "directedEdge", ou = "adjacencyList"): tells whether a directed edge occurs in the multi-graph represented by an adjacency list
areTheSame: signature(x = "adjacencyList", y = "adjacencyList"): x and y are the same adjacency list if they represent the same multi-graph
[: signature(x = "adjacencyList"): extracts the adjacency list of an induced subgraph
[[: signature(x = "adjacencyList"): extracts the character identifier of a vertex
coerce: signature(from = "incidenceList", to = "adjacencyList"): converts an incidence list to an adjacency list by dropping all but ordinary directed and undirected edges
coerce: signature(from = "incidenceMatrix", to = "adjacencyList"): converts an incidence matrix to an adjacency matrix by dropping hyper-edges
coerce: signature(from = "adjacencyMatrix", to = "adjacencyList"): converts an adjacency matrix to an adjacency list
+: signature(e1 = "adjacencyList", e2 = "vertexSet"): adds a vertex set to an adjacency list by making the new vertices isolated
-: signature(e1 = "adjacencyList", e2 = "vertexSet"): removes a vertex set from an adjacency list by dropping all edges involving the vertex set
+: signature(e1 = "adjacencyList", e2 = "undirectedEdge"): adds an ordinary undirected edge to an adjacency list
+: signature(e1 = "adjacencyList", e2 = "directedEdge"): adds an ordinary directed edge to an adjacency list
-: signature(e1 = "adjacencyList", e2 = "undirectedEdge"): removes an undirected edge from an adjacency list
-: signature(e1 = "adjacencyList", e2 = "directedEdge"): removes a directed edge from an adjacency list
*: signature(e1 = "adjacencyMatrix", e2 = "vertexSet"): restricts an adjacency matrix to a vertex set by dropping all edges involving vertices outside the vertex set

The pa, ch and ne constructor input lists are silently discarded if their length differs from the actual number of vertices (determined by id). All input numeric identifiers greater than this number are also silently discarded by the constructor. The id input to constructor is mandatory, since the constructor needs to identify vertices. In addition, at least one between pa and ch should be present, if directed edges have to be specified, and ne should be present, if undirected edges have to be specified. If both pa and ch are present, the union of the two corresponding multi-sets of edges is specified. If the neighbourhood relationship specified by ne is not symmetric, it is made symmetric by the constructor.

The names<- replacement method works only if the names to be assigned can be used to construct a vertexSet object having the right cardinality, otherwise the names are left unchanged and a warning message is given.

Jens Henrik Badsberg, Claus Dethlefsen, Luca La Rocca

adjacencyList and multiGraph-class

ClausDethlefsen/giRaph documentation built on May 25, 2019, 1:36 p.m.