/**
* Get data between two points in delta form.
*
* @param desc The data description.
* @param index The index to get data from.
* @return The requested data.
*/
private double getDataDeltaChange(final TemporalDataDescription desc, final int index) {
if (index == 0) {
return 0.0;
}
final TemporalPoint point = this.points.get(index);
final TemporalPoint previousPoint = this.points.get(index - 1);
return point.getData(desc.getIndex()) - previousPoint.getData(desc.getIndex());
}
/**
* Get data between two points in percent form.
*
* @param desc The data description.
* @param index The index to get data from.
* @return The requested data.
*/
private double getDataPercentChange(final TemporalDataDescription desc, final int index) {
if (index == 0) {
return 0.0;
}
final TemporalPoint point = this.points.get(index);
final TemporalPoint previousPoint = this.points.get(index - 1);
final double currentValue = point.getData(desc.getIndex());
final double previousValue = previousPoint.getData(desc.getIndex());
return (currentValue - previousValue) / previousValue;
}
/** Calculate how many input and output neurons will be needed for the current data. */
public void calculateNeuronCounts() {
this.inputNeuronCount = 0;
this.outputNeuronCount = 0;
for (final TemporalDataDescription desc : this.descriptions) {
if (desc.isInput()) {
this.inputNeuronCount += this.inputWindowSize;
}
if (desc.isPredict()) {
this.outputNeuronCount += this.predictWindowSize;
}
}
}
/**
* Generate input neural data for the specified index.
*
* @param index The index to generate neural data for.
* @return The input neural data generated.
*/
public BasicNeuralData generateInputNeuralData(final int index) {
if (index + this.inputWindowSize > this.points.size()) {
throw new TemporalError(
"Can't generate input temporal data " + "beyond the end of provided data.");
}
final BasicNeuralData result = new BasicNeuralData(this.inputNeuronCount);
int resultIndex = 0;
for (int i = 0; i < this.inputWindowSize; i++) {
int descriptionIndex = 0;
for (final TemporalDataDescription desc : this.descriptions) {
if (desc.isInput()) {
result.setData(resultIndex++, formatData(desc, index + i));
}
descriptionIndex++;
}
}
return result;
}
/**
* Format data according to the type specified in the description.
*
* @param desc The data description.
* @param index The index to format the data at.
* @return The formatted data.
*/
private double formatData(final TemporalDataDescription desc, final int index) {
final double[] result = new double[1];
switch (desc.getType()) {
case DELTA_CHANGE:
result[0] = getDataDeltaChange(desc, index);
break;
case PERCENT_CHANGE:
result[0] = getDataPercentChange(desc, index);
break;
case RAW:
result[0] = getDataRAW(desc, index);
break;
default:
throw new TemporalError("Unsupported data type.");
}
if (desc.getActivationFunction() != null) {
desc.getActivationFunction().activationFunction(result, 0, result.length);
}
return result[0];
}
/**
* Add a data description.
*
* @param desc The data description to add.
*/
public void addDescription(final TemporalDataDescription desc) {
if (this.points.size() > 0) {
final String str =
"Can't add anymore descriptions, there are " + "already temporal points defined.";
throw new TemporalError(str);
}
final int index = this.descriptions.size();
desc.setIndex(index);
this.descriptions.add(desc);
calculateNeuronCounts();
}
/**
* Get data between two points in raw form.
*
* @param desc The data description.
* @param index The index to get data from.
* @return The requested data.
*/
private double getDataRAW(final TemporalDataDescription desc, final int index) {
final TemporalPoint point = this.points.get(index - 1);
return point.getData(desc.getIndex());
}
