Example usage for org.apache.commons.math3.linear ArrayRealVector unitVector

Introduction

In this page you can find the example usage for org.apache.commons.math3.linear ArrayRealVector unitVector.

Prototype

public RealVector unitVector() throws MathArithmeticException 

Source Link

Document

Creates a unit vector pointing in the direction of this vector.

Usage

From source file:org.apache.solr.client.solrj.io.eval.UnitEvaluator.java

@Override
public Object doWork(Object value) throws IOException {
    if (null == value) {
        return null;
    } else if (value instanceof Matrix) {
        Matrix matrix = (Matrix) value;/*w  w  w. j  a  va 2  s. c o  m*/
        double[][] data = matrix.getData();
        double[][] unitData = new double[data.length][];
        for (int i = 0; i < data.length; i++) {
            double[] row = data[i];
            ArrayRealVector vector = new ArrayRealVector(row);
            double[] unitRow = vector.unitVector().toArray();
            unitData[i] = unitRow;
        }

        return new Matrix(unitData);
    } else if (value instanceof List) {
        List<Number> values = (List<Number>) value;
        double[] doubles = new double[values.size()];
        for (int i = 0; i < doubles.length; i++) {
            doubles[i] = values.get(i).doubleValue();
        }

        ArrayRealVector vector = new ArrayRealVector(doubles);
        RealVector unitVector = vector.unitVector();
        List<Number> unitList = new ArrayList(doubles.length);
        double[] unitArray = unitVector.toArray();
        for (double d : unitArray) {
            unitList.add(d);
        }

        return unitList;
    } else {
        throw new IOException("The unit function expects either a numeric array or matrix as a parameter");
    }
}

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