Example usage for weka.core Instance attribute

Introduction

In this page you can find the example usage for weka.core Instance attribute.

Prototype

public Attribute attribute(int index);

Source Link

Document

Returns the attribute with the given index.

Usage

From source file:tr.gov.ulakbim.jDenetX.streams.filters.AddNoiseFilter.java

License:Open Source License

public Instance nextInstance() {
    Instance inst = (Instance) this.inputStream.nextInstance().copy();
    for (int i = 0; i < inst.numAttributes(); i++) {
        double noiseFrac = i == inst.classIndex() ? this.classNoiseFractionOption.getValue()
                : this.attNoiseFractionOption.getValue();
        if (inst.attribute(i).isNominal()) {
            DoubleVector obs = (DoubleVector) this.attValObservers.get(i);
            if (obs == null) {
                obs = new DoubleVector();
                this.attValObservers.set(i, obs);
            }/*w  ww .j a  v a  2s .c  om*/
            int originalVal = (int) inst.value(i);
            if (!inst.isMissing(i)) {
                obs.addToValue(originalVal, inst.weight());
            }
            if ((this.random.nextDouble() < noiseFrac) && (obs.numNonZeroEntries() > 1)) {
                do {
                    inst.setValue(i, this.random.nextInt(obs.numValues()));
                } while (((int) inst.value(i) == originalVal) || (obs.getValue((int) inst.value(i)) == 0.0));
            }
        } else {
            GaussianEstimator obs = (GaussianEstimator) this.attValObservers.get(i);
            if (obs == null) {
                obs = new GaussianEstimator();
                this.attValObservers.set(i, obs);
            }
            obs.addObservation(inst.value(i), inst.weight());
            inst.setValue(i, inst.value(i) + this.random.nextGaussian() * obs.getStdDev() * noiseFrac);
        }
    }
    return inst;
}

From source file:tubesduaai.NB_030.java

@Override
public double classifyInstance(Instance instnc) throws Exception {
    // Pengklasifikasi instance baru
    int NUM_CLASSES = datas.classAttribute().numValues();
    //        System.out.println("------------------------------");
    //        System.out.println(datas.get(1));
    //        System.out.println(datas.get(1).stringValue(2));
    // Probability of classes
    int arg = 0;//from  ww w  .j  a  va  2s.  c  o m
    Double argmax = 0.0;
    Double temp = 1.0;
    for (int i = 0; i < NUM_CLASSES; i++) { // arg max (vj E enum.attributes(datas))
        // P(kelas)*P(atribut|kelas)
        temp = ((new Double(num[i])) / datas.numInstances());
        for (int j = 0; j < datas.numAttributes(); j++) {
            if (j != datas.classIndex()) {
                //                System.out.println("--------------");
                //                System.out.println(map.get(instnc.attribute(j).name()+instnc.stringValue(j)+datas.classAttribute().value(i)));
                temp *= map.get(
                        instnc.attribute(j).name() + instnc.stringValue(j) + datas.classAttribute().value(i));
            }
        }
        if (temp > argmax) {
            argmax = temp;
            arg = i;
        }
    }
    switch (arg) {
    case 0:
        return 0.0;
    case 1:
        return 1.0;
    case 2:
        return 2.0;
    default:
        return 0.0;
    }
}

From source file:wekimini.DataManager.java

public void setOutputValue(int index, int whichOutput, double val) {
    Instance i = allInstances.instance(index);
    if (i == null) {
        return;/*from   w w w  .  j a v  a2 s  . c  o  m*/
    }

    boolean changesNumberOfInstances = i.isMissing(numMetaData + numInputs + whichOutput);

    if (isDiscrete[whichOutput]) {
        int v = (int) val;
        Attribute a = i.attribute(numMetaData + numInputs + whichOutput);
        if (a.isNominal() && v >= 0 && v <= numClasses[whichOutput]) {
            i.setValue(numMetaData + numInputs + whichOutput, v);
        } else {
            logger.log(Level.SEVERE, "Attribute value out of range");
            //TODO: CHeck this
        }
    } else {
        //TODO insert error checking / range limiting for this version!
        i.setValue(numMetaData + numInputs + whichOutput, val);
    }
    if (changesNumberOfInstances) {
        setNumExamplesPerOutput(whichOutput, getNumExamplesPerOutput(whichOutput) + 1);
    }
}

From source file:wekimini.DataManager.java

public String getTimestampAsString(int index) {
    if (index >= 0 && index < allInstances.numInstances()) {
        Instance in = allInstances.instance(index);
        if (in != null) {
            return in.attribute(timestampIndex).formatDate(in.value(timestampIndex));
            // return in.value(timestampIndex);
        }//w w  w  .j a  va2s.  co m
    }
    return "error";
}