Java example source code file (TestGraphLoadingWeighted.java)

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Java - Java tags/keywords

classpathresource, comment, exception, igraph, ioexception, list, string, stringvertexfactory, test, testgraphloadingweighted, util, weightededgelineprocessor

The TestGraphLoadingWeighted.java Java example source code

package org.deeplearning4j.graph.data;

import org.apache.commons.lang3.ArrayUtils;
import org.deeplearning4j.graph.api.Edge;
import org.deeplearning4j.graph.api.IGraph;
import org.deeplearning4j.graph.data.impl.WeightedEdgeLineProcessor;
import org.deeplearning4j.graph.graph.Graph;
import org.deeplearning4j.graph.vertexfactory.StringVertexFactory;
import org.deeplearning4j.graph.vertexfactory.VertexFactory;
import org.junit.Test;
import org.nd4j.linalg.io.ClassPathResource;

import java.io.IOException;
import java.util.List;

import static junit.framework.TestCase.assertTrue;
import static org.junit.Assert.assertEquals;

public class TestGraphLoadingWeighted {

    @Test
    public void testWeightedDirected() throws IOException{

        String path = new ClassPathResource("WeightedGraph.txt").getFile().getAbsolutePath();
        int numVertices = 9;
        String delim = ",";
        String[] ignoreLinesStartingWith = new String[]{"//"};  //Comment lines start with "//"

        IGraph<String,Double> graph = GraphLoader.loadWeightedEdgeListFile(path,numVertices,delim,true,ignoreLinesStartingWith);

        assertEquals(numVertices, graph.numVertices());

        int[] vertexOutDegrees = {2,2,1,2,2,1,1,1,1};
        for( int i=0; i<numVertices; i++ ) assertEquals(vertexOutDegrees[i],graph.getVertexDegree(i));
        int[][] edges = new int[][]{
                {1, 3},     //0->1 and 1->3
                {2, 4},     //1->2 and 1->4
                {5},        //etc
                {4, 6},
                {5, 7},
                {8},
                {7},
                {8},
                {0}
        };
        double[][] edgeWeights = new double[][]{
                {1, 3},
                {12, 14},
                {25},
                {34, 36},
                {45, 47},
                {58},
                {67},
                {78},
                {80}
        };

        for( int i=0; i<numVertices; i++ ){
            List<Edge edgeList = graph.getEdgesOut(i);
            assertEquals(edges[i].length, edgeList.size());
            for(Edge<Double> e : edgeList){
                int from = e.getFrom();
                int to = e.getTo();
                double weight = e.getValue();
                assertEquals(i,from);
                assertTrue(ArrayUtils.contains(edges[i],to));
                int idx = ArrayUtils.indexOf(edges[i],to);
                assertEquals(edgeWeights[i][idx],weight,0.0);
            }
        }

        System.out.println(graph);
    }


    @Test
    public void testWeightedDirectedV2() throws Exception {

        String path = new ClassPathResource("WeightedGraph.txt").getFile().getAbsolutePath();
        int numVertices = 9;
        String delim = ",";
        boolean directed = true;
        String[] ignoreLinesStartingWith = new String[]{"//"};  //Comment lines start with "//"

        IGraph<String,Double> graph = GraphLoader.loadWeightedEdgeListFile(path,numVertices,delim,directed,false,ignoreLinesStartingWith);

        assertEquals(numVertices, graph.numVertices());

        //EdgeLineProcessor: used to convert lines -> edges
        EdgeLineProcessor<Double> edgeLineProcessor = new WeightedEdgeLineProcessor(delim,directed,ignoreLinesStartingWith);
        //Vertex factory: used to create vertex objects, given an index for the vertex
        VertexFactory<String> vertexFactory = new StringVertexFactory();

        Graph<String,Double> graph2 = GraphLoader.loadGraph(path,edgeLineProcessor,vertexFactory,numVertices,false);

        assertEquals(graph,graph2);
    }

}