Example usage for org.apache.commons.math3.ml.distance ChebyshevDistance compute

List of usage examples for org.apache.commons.math3.ml.distance ChebyshevDistance compute

Introduction

In this page you can find the example usage for org.apache.commons.math3.ml.distance ChebyshevDistance compute.

Prototype

public double compute(double[] a, double[] b) 

Source Link

Usage

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

@Override
public Object doWork(Object first, Object second) throws IOException {
    if (null == first) {
        throw new IOException(String.format(Locale.ROOT,
                "Invalid expression %s - null found for the first value", toExpression(constructingFactory)));
    }/*from   w ww. ja  v a2s. c  o m*/
    if (null == second) {
        throw new IOException(String.format(Locale.ROOT,
                "Invalid expression %s - null found for the second value", toExpression(constructingFactory)));
    }
    if (!(first instanceof List<?>)) {
        throw new IOException(String.format(Locale.ROOT,
                "Invalid expression %s - found type %s for the first value, expecting a list of numbers",
                toExpression(constructingFactory), first.getClass().getSimpleName()));
    }
    if (!(second instanceof List<?>)) {
        throw new IOException(String.format(Locale.ROOT,
                "Invalid expression %s - found type %s for the second value, expecting a list of numbers",
                toExpression(constructingFactory), first.getClass().getSimpleName()));
    }

    ChebyshevDistance distance = new ChebyshevDistance();
    return distance.compute(
            ((List) first).stream().mapToDouble(value -> ((BigDecimal) value).doubleValue()).toArray(),
            ((List) second).stream().mapToDouble(value -> ((BigDecimal) value).doubleValue()).toArray());
}