Example usage for org.apache.mahout.cf.taste.hadoop.item VectorAndPrefsWritable VectorAndPrefsWritable

Introduction

In this page you can find the example usage for org.apache.mahout.cf.taste.hadoop.item VectorAndPrefsWritable VectorAndPrefsWritable.

Prototype

public VectorAndPrefsWritable(Vector vector, List<Long> userIDs, List<Float> values) 

Source Link

Usage

From source file:com.skp.experiment.common.mapreduce.ToVectorAndPrefReducer.java

License:Apache License

@Override
protected void reduce(IntWritable key, Iterable<VectorOrPrefWritable> values, Context context)
        throws IOException, InterruptedException {

    List<Long> userIDs = Lists.newArrayList();
    List<Float> prefValues = Lists.newArrayList();
    Vector similarityMatrixColumn = null;
    for (VectorOrPrefWritable value : values) {
        if (value.getVector() == null) {
            // Then this is going into list
            userIDs.add(value.getUserID());
            prefValues.add(value.getValue());
        } else {/*from  w w  w.  j av  a2 s  . co  m*/
            // Then this is going into vector
            if (similarityMatrixColumn != null) {
                throw new IllegalStateException(" " + key.get());
            }
            similarityMatrixColumn = value.getVector();
        }
    }

    if (similarityMatrixColumn == null) {
        return;
    }

    VectorAndPrefsWritable vectorAndPrefs = new VectorAndPrefsWritable(similarityMatrixColumn, userIDs,
            prefValues);
    context.write(key, vectorAndPrefs);
}

---