redContext = DummyRecordWriter.build(reducer, conf, redWriter,
Text.class, VertexWritable.class);
// perform the reduction
for (Text key : comWriter.getKeys()) {
reducer.reduce(key, comWriter.getValue(key), redContext);
}
// now, check that the affinity matrix is correctly formed
for (IntWritable row : redWriter.getKeys()) {
List<VectorWritable> results = redWriter.getValue(row);