edu.uci.ics.jung.io
Class MatrixFile<V,E>

java.lang.Object
  edu.uci.ics.jung.io.MatrixFile<V,E>

All Implemented Interfaces:

GraphFile<V,E>

public class MatrixFile<V,E>
extends Object
implements GraphFile<V,E>

Basic I/O handler for ascii matrix files. An ascii matrix is simply a square matrix where 0 values for cell (i,j) indicates no edge exists between vertex i and vertex j and non-zero values indicates there is an edge. If a non-null weight key is specified then it will be used to treat the non-zero values as a weight stored in the edges' user data keyed off the specified weight key value.

When loading a graph from a file, a symmetric graph will result in the construction of an undirected sparse graph while a non-symmetric graph will result in the construction of a directed sparse graph.

For example the following ascii matrix when loaded using the code:
MatrixFile mf = new MatrixFile(null);
Graph g = mf.load(filename);
will produce an undirected sparse matrix with no weights:

 0 1 0 1
 1 0 0 1
 0 0 0 0
 1 1 0 0
 

whereas the following ascii matrix when loaded using the code:
MatrixFile mf = new MatrixFile("WEIGHT");
Graph g = mf.load(filename);
will produce a directed sparse matrix with double weight values stored in the edges user data under the key "WEIGHT" :

 0 .5 10 0
 0 1 0 0
 0 0 0 -30
 5 0 0 0
 

Author:

Scott, Tom Nelson - converted to jung2

Constructor Summary

MatrixFile(Map<E,Number> weightKey, org.apache.commons.collections15.Factory<? extends Graph<V,E>> graphFactory, org.apache.commons.collections15.Factory<V> vertexFactory, org.apache.commons.collections15.Factory<E> edgeFactory)
Constructs MatrixFile instance.

Method Summary

Graph<V,E>	load(BufferedReader reader) Loads a graph from an input reader
Graph<V,E>	load(String filename) Loads a graph from a file.
void	save(Graph<V,E> graph, String filename) Saves a graph to a file

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MatrixFile

public MatrixFile(Map<E,Number> weightKey,
                  org.apache.commons.collections15.Factory<? extends Graph<V,E>> graphFactory,
                  org.apache.commons.collections15.Factory<V> vertexFactory,
                  org.apache.commons.collections15.Factory<E> edgeFactory)

Constructs MatrixFile instance. If weightKey is not null then, it will attempt to use that key to store and retreive weights from the edges' UserData.

Method Detail

load

public Graph<V,E> load(BufferedReader reader)
                throws IOException

Loads a graph from an input reader

Parameters:

reader - the input reader

Returns:

the graph

Throws:

IOException

load

public Graph<V,E> load(String filename)

Loads a graph from a file.

Specified by:

load in interface GraphFile<V,E>

Parameters:

filename - the location and name of the file

Returns:

the graph

See Also:

GraphFile.load(java.lang.String)

save

public void save(Graph<V,E> graph,
                 String filename)

Saves a graph to a file

Specified by:

save in interface GraphFile<V,E>

Parameters:

graph - the location and name of the file

filename - the graph

See Also:

GraphFile.save(edu.uci.ics.jung.graph.Graph, java.lang.String)