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Using the arff file to store data

I use this example to create my .arff file for my weka projext enter the link description here .

double[][] data = {{4058.0, 4059.0, 4060.0, 214.0, 1710.0, 2452.0, 2473.0, 2474.0, 2475.0, 2476.0, 2477.0, 2478.0, 2688.0, 2905.0, 2906.0, 2907.0, 2908.0, 2909.0, 2950.0, 2969.0, 2970.0, 3202.0, 3342.0, 3900.0, 4007.0, 4052.0, 4058.0, 4059.0, 4060.0}, 
                       {19.0, 20.0, 21.0, 31.0, 103.0, 136.0, 141.0, 142.0, 143.0, 144.0, 145.0, 146.0, 212.0, 243.0, 244.0, 245.0, 246.0, 247.0, 261.0, 270.0, 271.0, 294.0, 302.0, 340.0, 343.0, 354.0, 356.0, 357.0, 358.0}};

    int numInstances = data[0].length;

    FastVector atts = new FastVector();
    ArrayList<Instance> instances = new ArrayList<Instance>();
    for (int dim = 0; dim < 2; dim++) {
        // Create new attribute / dimension
        Attribute current = new Attribute("Attribute" + dim, dim);
        // Create an instance for each data object


        if (dim == 0) {
            for (int obj = 0; obj < numInstances; obj++) {
                instances.add(new SparseInstance(0));

            }
        }

        // Fill the value of dimension "dim" into each object
        for (int obj = 0; obj < numInstances; obj++) {
            instances.get(obj).setValue(current, data[dim][obj]);
            System.out.println(instances.get(obj));
        }

        // Add attribute to total attributes
        atts.addElement(current);

    }

     // Create new dataset
    Instances newDataset = new Instances("Dataset", atts, instances.size());

    // Fill in data objects
    for (Instance inst : instances) {
        newDataset.add(inst);       
    }

    BufferedWriter writer = new BufferedWriter(new FileWriter("test.arff"));
    writer.write(newDataset.toString());
    writer.flush();
    writer.close();
}

I noticed that the result format puts the rows element in the vector in the columns of the .arff file. I want to put the whole line in the first line of the .arff file. How can i do this? For my case, the last column of 2d is a row data label.

Expected result for my arff file:

4058.0, 4059.0, 4060.0, 214.0, 1710.0, 2452.0, 2473.0, 2474.0, 2475.0, 2476.0, 2477.0, 2478.0, 2688.0, 2905.0, 2906.0, 2907.0, 2908.0, 2909.0, 2950.0, 2969.0, 2970.0, 3202.0, 3342.0, 3900.0, 4007.0, 4052.0, 4058.0, 4059.0, 4060.0, 1 // for example the first row
 19.0, 20.0, 21.0, 31.0, 103.0, 136.0, 141.0, 142.0, 143.0, 144.0, 145.0, 146.0, 212.0,  
 243.0, 244.0, 245.0, 246.0, 247.0, 261.0, 270.0, 271.0, 294.0, 302.0, 340.0, 343.0, 
 354.0, 356.0, 357.0, 358.0, 0 // the second row.
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1 answer

( 29 , ). , ( , 29 ):

double[][] data = {
                    {4058.0, 4059.0, ... }, /* first instance */
                    {19.0, 20.0, ... }      /* second instance */
                  };

int numAtts = data[0].length;
FastVector atts = new FastVector(numAtts);
for (int att = 0; att < numAtts; att++)
{
    atts.addElement(new Attribute("Attribute" + att, att));
}

int numInstances = data.length;
Instances dataset = new Instances("Dataset", atts, numInstances);
for (int inst = 0; inst < numInstances; inst++)
{
    dataset.add(new Instance(1.0, data[inst]));
}

BufferedWriter writer = new BufferedWriter(new FileWriter("test.arff"));
writer.write(dataset.toString());
writer.flush();
writer.close();

SparseInstance Instance, . , Weka 3.7 Instance , DenseInstance. , FastVector Java ArrayList.

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