public void ComputeFeatures()
{
List <double> diffX = Diff(X);
List <double> diffY = Diff(Y);
List <double> diffTimestamp = Diff(Timestamp);
// Article base features
// Stroke length
double strokeLength = Pythagorean(diffX, diffY);
Features.Add("length", strokeLength);
// Stroke speed -> Avg
// length / (last touch features time - first touch features time)
double speedMean = strokeLength / (Timestamp.Last() - Timestamp.First());
Features.Add("mean speed", speedMean);
// Directness index (distance between start and end -> ignores path) -> Avg
double directness = Distance(X.First(), X.Last(), Y.First(), Y.Last());
Features.Add("directness", directness);
// Contact Area (Touch Major) -> Avg
double contactArea = TouchMajor.Average();
Features.Add("mean contact area", contactArea);
//double contactAreaMin = TouchMajor.Min();
//Features.Add("min contact area", contactAreaMin);
//double contactAreaMax = TouchMajor.Max();
//Features.Add("max contact area", contactAreaMax);
//double contactAreaStd = Measures.StandardDeviation(TouchMajor.ToArray(), false);
//Features.Add("std max contact area", contactAreaStd);
}