Example usage for weka.core SparseInstance toString

Introduction

In this page you can find the example usage for weka.core SparseInstance toString.

Prototype

@Override
public String toString() 

Source Link

Document

Returns the description of one instance.

Usage

From source file:mulan.data.ConverterLibSVM.java

License:Open Source License

/**
 * Converts a multi-label dataset from LibSVM format to the format
 * that is compatible with Mulan. It constructs one ARFF and one XML file. 
 *
 * @param path the directory that contains the source file and will contain 
 * the target files/*from   ww  w  .ja v a  2 s.  c o  m*/
 * @param sourceFilename the name of the source file
 * @param relationName the relation name of the arff file that will be 
 * constructed
 * @param targetFilestem the filestem for the target files (.arff and .xml)
 */
public static void convertFromLibSVM(String path, String sourceFilename, String targetFilestem,
        String relationName) {
    BufferedReader aReader = null;
    BufferedWriter aWriter = null;

    int numLabels = 0;
    int numAttributes = 0;
    int numInstances = 0;
    double meanParsedAttributes = 0;

    // Calculate number of labels and attributes

    String Line = null;
    try {
        aReader = new BufferedReader(new FileReader(path + sourceFilename));

        while ((Line = aReader.readLine()) != null) {
            numInstances++;

            StringTokenizer strTok = new StringTokenizer(Line, " ");
            while (strTok.hasMoreTokens()) {
                String token = strTok.nextToken();

                if (token.indexOf(":") == -1) {
                    // parse label info
                    StringTokenizer labelTok = new StringTokenizer(token, ",");
                    while (labelTok.hasMoreTokens()) {
                        String strLabel = labelTok.nextToken();
                        int intLabel = Integer.parseInt(strLabel);
                        if (intLabel > numLabels) {
                            numLabels = intLabel;
                        }
                    }
                } else {
                    // parse attribute info
                    meanParsedAttributes++;
                    StringTokenizer attrTok = new StringTokenizer(token, ":");
                    String strAttrIndex = attrTok.nextToken();
                    int intAttrIndex = Integer.parseInt(strAttrIndex);
                    if (intAttrIndex > numAttributes) {
                        numAttributes = intAttrIndex;
                    }
                }
            }
        }

        numLabels++;

        System.out.println("Number of attributes: " + numAttributes);
        System.out.println("Number of instances: " + numInstances);
        System.out.println("Number of classes: " + numLabels);

        System.out.println("Constructing XML file... ");
        LabelsMetaDataImpl meta = new LabelsMetaDataImpl();
        for (int label = 0; label < numLabels; label++) {
            meta.addRootNode(new LabelNodeImpl("Label" + (label + 1)));
        }

        String labelsFilePath = path + targetFilestem + ".xml";
        try {
            LabelsBuilder.dumpLabels(meta, labelsFilePath);
            System.out.println("Done!");
        } catch (LabelsBuilderException e) {
            File labelsFile = new File(labelsFilePath);
            if (labelsFile.exists()) {
                labelsFile.delete();
            }
            System.out.println("Construction of labels XML failed!");
        }

        meanParsedAttributes /= numInstances;
        boolean Sparse = false;
        if (meanParsedAttributes < numAttributes) {
            Sparse = true;
            System.out.println("Dataset is sparse.");
        }

        // Define Instances class to hold data
        ArrayList<Attribute> attInfo = new ArrayList<Attribute>(numAttributes + numLabels);
        Attribute[] att = new Attribute[numAttributes + numLabels];

        for (int i = 0; i < numAttributes; i++) {
            att[i] = new Attribute("Att" + (i + 1));
            attInfo.add(att[i]);
        }
        ArrayList<String> ClassValues = new ArrayList<String>(2);
        ClassValues.add("0");
        ClassValues.add("1");
        for (int i = 0; i < numLabels; i++) {
            att[numAttributes + i] = new Attribute("Label" + (i + 1), ClassValues);
            attInfo.add(att[numAttributes + i]);
        }

        // Re-read file and convert into multi-label arff
        int countInstances = 0;

        aWriter = new BufferedWriter(new FileWriter(path + targetFilestem + ".arff"));
        Instances data = new Instances(relationName, attInfo, 0);
        aWriter.write(data.toString());

        aReader = new BufferedReader(new FileReader(path + sourceFilename));

        while ((Line = aReader.readLine()) != null) {
            countInstances++;

            // set all  values to 0
            double[] attValues = new double[numAttributes + numLabels];
            Arrays.fill(attValues, 0);

            Instance tempInstance = new DenseInstance(1, attValues);
            tempInstance.setDataset(data);

            // separate class info from attribute info
            // ensure class info exists
            StringTokenizer strTok = new StringTokenizer(Line, " ");

            while (strTok.hasMoreTokens()) {
                String token = strTok.nextToken();

                if (token.indexOf(":") == -1) {
                    // parse label info
                    StringTokenizer labelTok = new StringTokenizer(token, ",");
                    while (labelTok.hasMoreTokens()) {
                        String strLabel = labelTok.nextToken();
                        int intLabel = Integer.parseInt(strLabel);
                        tempInstance.setValue(numAttributes + intLabel, 1);
                    }
                } else {
                    // parse attribute info
                    StringTokenizer AttrTok = new StringTokenizer(token, ":");
                    String strAttrIndex = AttrTok.nextToken();
                    String strAttrValue = AttrTok.nextToken();
                    tempInstance.setValue(Integer.parseInt(strAttrIndex) - 1, Double.parseDouble(strAttrValue));
                }
            }

            if (Sparse) {
                SparseInstance tempSparseInstance = new SparseInstance(tempInstance);
                aWriter.write(tempSparseInstance.toString() + "\n");
            } else {
                aWriter.write(tempInstance.toString() + "\n");
            }

        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            if (aReader != null) {
                aReader.close();
            }
            if (aWriter != null) {
                aWriter.close();
            }
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

---