Example usage for weka.core.stats NumericStats computeDerived

Introduction

In this page you can find the example usage for weka.core.stats NumericStats computeDerived.

Prototype

public void computeDerived() 

Source Link

Document

Compute the derived statistics

Usage

From source file:distributed.core.DistributedUtils.java

License:Open Source License

public static NumericStats getNumericAttributeStatsSparse(Instances denormalized, int attIndex) {
    NumericStats ns = new NumericStats(denormalized.attribute(attIndex).name());

    for (int j = 0; j < denormalized.numInstances(); j++) {
        double value = denormalized.instance(j).value(attIndex);

        if (Utils.isMissingValue(value) || value == 0) {
            ns.getStats()[ArffSummaryNumericMetric.MISSING.ordinal()]++;
        } else {/*from www  . ja v a 2s.  c  o  m*/
            ns.getStats()[ArffSummaryNumericMetric.COUNT.ordinal()]++;
            ns.getStats()[ArffSummaryNumericMetric.SUM.ordinal()] += value;
            ns.getStats()[ArffSummaryNumericMetric.SUMSQ.ordinal()] += value * value;
            if (Double.isNaN(ns.getStats()[ArffSummaryNumericMetric.MIN.ordinal()])) {
                ns.getStats()[ArffSummaryNumericMetric.MIN
                        .ordinal()] = ns.getStats()[ArffSummaryNumericMetric.MAX.ordinal()] = value;
            } else if (value < ns.getStats()[ArffSummaryNumericMetric.MIN.ordinal()]) {
                ns.getStats()[ArffSummaryNumericMetric.MIN.ordinal()] = value;
            } else if (value > ns.getStats()[ArffSummaryNumericMetric.MAX.ordinal()]) {
                ns.getStats()[ArffSummaryNumericMetric.MAX.ordinal()] = value;
            }
        }
    }

    ns.computeDerived();

    return ns;
}

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From source file:distributed.core.DistributedUtils.java

License:Open Source License

public static Instances makeHeaderWithSummaryAtts(Instances denormalized, boolean treatZerosAsMissing) {
    Instances header = new Instances(denormalized, 0);

    for (int i = 0; i < denormalized.numAttributes(); i++) {
        AttributeStats stats = denormalized.attributeStats(i);
        if (denormalized.attribute(i).isNumeric()) {
            NumericStats ns = new NumericStats(denormalized.attribute(i).name());
            if (!treatZerosAsMissing) {
                ns.getStats()[ArffSummaryNumericMetric.MIN.ordinal()] = stats.numericStats.min;
                ns.getStats()[ArffSummaryNumericMetric.MAX.ordinal()] = stats.numericStats.max;
                ns.getStats()[ArffSummaryNumericMetric.COUNT.ordinal()] = stats.numericStats.count;
                ns.getStats()[ArffSummaryNumericMetric.SUM.ordinal()] = stats.numericStats.sum;
                ns.getStats()[ArffSummaryNumericMetric.SUMSQ.ordinal()] = stats.numericStats.sumSq;
                ns.getStats()[ArffSummaryNumericMetric.MISSING.ordinal()] = stats.missingCount;

                ns.computeDerived();
            } else {
                ns = getNumericAttributeStatsSparse(denormalized, i);
            }//from  w w w .  j a  v  a2s. c o  m

            Attribute newAtt = ns.makeAttribute();
            header.insertAttributeAt(newAtt, header.numAttributes());
        } else if (denormalized.attribute(i).isNominal()) {
            NominalStats nom = new NominalStats(denormalized.attribute(i).name());
            nom.setNumMissing(stats.missingCount);

            double[] labelFreqs = stats.nominalWeights;
            for (int j = 0; j < denormalized.attribute(i).numValues(); j++) {
                nom.add(denormalized.attribute(i).value(j), labelFreqs[j]);
            }

            Attribute newAtt = nom.makeAttribute();
            header.insertAttributeAt(newAtt, header.numAttributes());
        }
    }

    return header;
}

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