/// <summary>
/// Classify the input.
/// </summary>
/// <param name="input">The input to classify.</param>
/// <returns>The classification.</returns>
public int Classify(IMLData input)
{
if (_classificationTarget < 0 || _classificationTarget >= _events.Count)
{
throw new BayesianError("Must specify classification target by calling setClassificationTarget.");
}
int[] d = DetermineClasses(input);
// properly tag all of the events
for (int i = 0; i < _events.Count; i++)
{
BayesianEvent e = _events[i];
if (i == _classificationTarget)
{
Query.DefineEventType(e, EventType.Outcome);
}
else if (_inputPresent[i])
{
Query.DefineEventType(e, EventType.Evidence);
Query.SetEventValue(e, d[i]);
}
else
{
Query.DefineEventType(e, EventType.Hidden);
Query.SetEventValue(e, d[i]);
}
}
// loop over and try each outcome choice
BayesianEvent outcomeEvent = _events[_classificationTarget];
_classificationProbabilities = new double[outcomeEvent.Choices.Count];
for (int i = 0; i < outcomeEvent.Choices.Count; i++)
{
Query.SetEventValue(outcomeEvent, i);
Query.Execute();
_classificationProbabilities[i] = Query.Probability;
}
return(EngineArray.MaxIndex(_classificationProbabilities));
}
/// <summary>
/// Compute the output from this network.
/// </summary>
///
/// <param name="input">The input to the network.</param>
/// <returns>The output from the network.</returns>
public override sealed IMLData Compute(IMLData input)
{
var xout = new double[OutputCount];
double psum = 0.0d;
int r = -1;
foreach (IMLDataPair pair in _samples)
{
r++;
if (r == Exclude)
{
continue;
}
double dist = 0.0d;
for (int i = 0; i < InputCount; i++)
{
double diff = input[i] - pair.Input[i];
diff /= _sigma[i];
dist += diff * diff;
}
if (Kernel == PNNKernelType.Gaussian)
{
dist = Math.Exp(-dist);
}
else if (Kernel == PNNKernelType.Reciprocal)
{
dist = 1.0d / (1.0d + dist);
}
if (dist < 1.0e-40d)
{
dist = 1.0e-40d;
}
if (OutputMode == PNNOutputMode.Classification)
{
var pop = (int)pair.Ideal[0];
xout[pop] += dist;
}
else if (OutputMode == PNNOutputMode.Unsupervised)
{
for (int i = 0; i < InputCount; i++)
{
xout[i] += dist * pair.Input[i];
}
psum += dist;
}
else if (OutputMode == PNNOutputMode.Regression)
{
for (int i = 0; i < OutputCount; i++)
{
xout[i] += dist * pair.Ideal[i];
}
psum += dist;
}
}
if (OutputMode == PNNOutputMode.Classification)
{
psum = 0.0d;
for (int i = 0; i < OutputCount; i++)
{
if (_priors[i] >= 0.0d)
{
xout[i] *= _priors[i] / _countPer[i];
}
psum += xout[i];
}
if (psum < 1.0e-40d)
{
psum = 1.0e-40d;
}
for (int i = 0; i < OutputCount; i++)
{
xout[i] /= psum;
}
IMLData result = new BasicMLData(1);
result[0] = EngineArray.MaxIndex(xout);
return(result);
}
else if (OutputMode == PNNOutputMode.Unsupervised)
{
for (int i = 0; i < InputCount; i++)
{
xout[i] /= psum;
}
}
else if (OutputMode == PNNOutputMode.Regression)
{
for (int i = 0; i < OutputCount; i++)
{
xout[i] /= psum;
}
}
return(new BasicMLData(xout));
}
/// <summary>
/// Determine the winner for the specified input. This is the number of the
/// winning neuron.
/// </summary>
///
/// <param name="input">The input patter to present to the neural network.</param>
/// <returns>The winning neuron.</returns>
public int Winner(IMLData input)
{
IMLData output = Compute(input);
return(EngineArray.MaxIndex(output));
}
/// <inheritdoc/>
public int Classify(IMLData input)
{
IMLData output = Compute(input);
return(EngineArray.MaxIndex(output));
}
/// <inheritdoc/>
public int Classify(IMLData input)
{
IMLData result = Compute(input);
return(EngineArray.MaxIndex(result.Data));
}
