Java Code Examples for weka.core.Instances#setRelationName()

@Override
protected Instances determineOutputFormat(Instances inputFormat) throws Exception {

    Instances output = new Instances(inputFormat,0);
    output.deleteAttributeAt(0);
    output.setRelationName("goreckiDerivative_"+output.relationName());
    for(int a = 0; a < output.numAttributes()-1; a++){
        output.renameAttribute(a, "derivative_"+a);
    }

    return output;

}
 

/**
  * Sets the format of the input instances.
  *
  * @param instanceInfo an Instances object containing the input instance
  * structure (any instances contained in the object are ignored - only the
  * structure is required).
  * @return true if the outputFormat may be collected immediately
  * @throws Exception if the inputFormat can't be set successfully 
  */ 
 public boolean setInputFormat(Instances instanceInfo) throws Exception {
   
   super.setInputFormat(instanceInfo);

   int[] attsToDelete = new int[instanceInfo.numAttributes()];
   int numToDelete = 0;
   for (int i=0; i<instanceInfo.numAttributes(); i++) {
     if (i == instanceInfo.classIndex()) {
       if (!m_invert) {
         continue; // skip class
       } else {
         attsToDelete[numToDelete++] = i; // Need to keep the class even if selection is inverted          
       }
     }
     if (instanceInfo.attribute(i).type() == m_attTypeToDelete)
attsToDelete[numToDelete++] = i;
   }

   int[] finalAttsToDelete = new int[numToDelete];
   System.arraycopy(attsToDelete, 0, finalAttsToDelete, 0, numToDelete);
   
   m_attributeFilter.setAttributeIndicesArray(finalAttsToDelete);
   m_attributeFilter.setInvertSelection(m_invert);
   
   boolean result = m_attributeFilter.setInputFormat(instanceInfo);
   Instances afOutputFormat = m_attributeFilter.getOutputFormat();
   
   // restore old relation name to hide attribute filter stamp
   afOutputFormat.setRelationName(instanceInfo.relationName());

   setOutputFormat(afOutputFormat);
   return result;
 }
 

/**
  * Determines the output format based on the input format and returns 
  * this. In case the output format cannot be returned immediately, i.e.,
  * hasImmediateOutputFormat() returns false, then this method will called
  * from batchFinished() after the call of preprocess(Instances), in which,
  * e.g., statistics for the actual processing step can be gathered.
  *
  * @param inputFormat     the input format to base the output format on
  * @return                the output format
  * @throws Exception      in case the determination goes wrong
  */
 protected Instances determineOutputFormat(Instances inputFormat) throws Exception {
   int			i;
   int[]		indices;
   StringBuilder	order;
   Instances		output;
   
   m_AttributeIndices.setUpper(inputFormat.numAttributes() - 1);
   order   = new StringBuilder();
   indices = m_AttributeIndices.getSelection();
   if (indices.length == 0)
     throw new WekaException("No attributes defined as class attributes!");
   for (i = 0; i < indices.length; i++) {
     if (i > 0)
order.append(",");
     order.append("" + (indices[i]+1));
   }
   for (i = 0; i < inputFormat.numAttributes(); i++) {
     if (m_AttributeIndices.isInRange(i))
continue;
     order.append(",");
     order.append("" + (i+1));
   }
   m_Reorder.setAttributeIndices(order.toString());
   m_Reorder.setInputFormat(inputFormat);
   
   output = m_Reorder.getOutputFormat();
   output.setClassIndex(indices.length);
   output.setRelationName("-C " + indices.length);
   
   return output;
 }
 

/**
  * Signify that this batch of input to the filter is finished.
  *
  * @return true if there are instances pending output
  * @throws Exception if no input format defined
  */  
 public boolean batchFinished() throws Exception {

   if (getInputFormat() == null) {
     throw new IllegalStateException("No input instance format defined");
   }
   if (m_removeFilter == null) {

     // establish attributes to remove from first batch

     Instances toFilter = getInputFormat();
     int[] attsToDelete = new int[toFilter.numAttributes()];
     int numToDelete = 0;
     for(int i = 0; i < toFilter.numAttributes(); i++) {
if (i==toFilter.classIndex()) continue; // skip class
AttributeStats stats = toFilter.attributeStats(i);
if (stats.missingCount == toFilter.numInstances()) {
  attsToDelete[numToDelete++] = i;
} else if (stats.distinctCount < 2) {
  // remove constant attributes
  attsToDelete[numToDelete++] = i;
} else if (toFilter.attribute(i).isNominal()) {
  // remove nominal attributes that vary too much
  double variancePercent = (double) stats.distinctCount
    / (double)(stats.totalCount - stats.missingCount) * 100.0;
  if (variancePercent > m_maxVariancePercentage) {
      attsToDelete[numToDelete++] = i;
  }
}
     }
     
     int[] finalAttsToDelete = new int[numToDelete];
     System.arraycopy(attsToDelete, 0, finalAttsToDelete, 0, numToDelete);
     
     m_removeFilter = new Remove();
     m_removeFilter.setAttributeIndicesArray(finalAttsToDelete);
     m_removeFilter.setInvertSelection(false);
     m_removeFilter.setInputFormat(toFilter);
     
     for (int i = 0; i < toFilter.numInstances(); i++) {
m_removeFilter.input(toFilter.instance(i));
     }
     m_removeFilter.batchFinished();

     Instance processed;
     Instances outputDataset = m_removeFilter.getOutputFormat();
   
     // restore old relation name to hide attribute filter stamp
     outputDataset.setRelationName(toFilter.relationName());
   
     setOutputFormat(outputDataset);
     while ((processed = m_removeFilter.output()) != null) {
processed.setDataset(outputDataset);
push(processed);
     }
   }
   flushInput();
   
   m_NewBatch = true;
   return (numPendingOutput() != 0);
 }
 

/**
 * Fixes the relation name by adding the "-C" attribute to it if necessary.
 *
 * @param data the dataset to fix
 * @param numClassAtts the number of class attributes (0 for none, >0 for attributes at start, <0 for attributes at end)
 */
public static void fixRelationName(Instances data, int numClassAtts) {
	if (data.relationName().indexOf(":") == -1)
		data.setRelationName(data.relationName() + ": -C " + numClassAtts);
}