/// <summary>
/// Initializes a new instance of the <see cref="FitLine"/> class.
/// </summary>
/// <param name="fitPoints">
/// The points to calculate the fit FitLine from
/// </param>
/// <param name="outlierThreshold">
/// The cook's distance threshold for a point to be identified as outliers.
/// </param>
public FitLine()
{
this.Mse = 0;
this.RSquared = 0;
this.Slope = 0;
this.Intercept = 0;
this.outlierCollection = new HashSet<FitlinePoint>();
this.fitPointCollection = new List<FitlinePoint>();
this.state = FitlineState.Observing;
}
public void RemovePoint(ContinuousXYPoint point)
{
this.fitPointCollection.Remove(new FitlinePoint(point));
this.state = FitlineState.Observing;
}
/// <summary>
/// Refit a group of points to the fit line.
/// </summary>
/// <param name="xyPoints">
/// The xy points.
/// </param>
public virtual void PerformRegression(IEnumerable<FitlinePoint> xyPoints)
{
IList<FitlinePoint> fitlinePoints = xyPoints as IList<FitlinePoint> ?? xyPoints.ToList();
this.LeastSquaresFitdLinear(fitlinePoints);
this.fitPointCollection.Clear();
this.fitPointCollection.AddRange(fitlinePoints);
this.outlierCollection.Clear();
this.state = FitlineState.ModelComplete;
}
/// <summary>
/// Using current fits points stored in the fitline to initiate regression
/// </summary>
/// <param name="xyPoints">
/// The xy points.
/// </param>
public virtual void PerformRegression()
{
this.LeastSquaresFitdLinear(this.FitPointCollection);
this.state = FitlineState.ModelComplete;
}
/// <exception cref="Exception">A delegate callback throws an exception.</exception>
public void DiagnoseRegression(Func<FitlinePoint, double> weightFunc = null)
{
// Calculate diagnostic information
if (this.state >= FitlineState.ModelComplete)
{
double mse = this.CalculateMSE();
double r2 = weightFunc == null? this.CalculatedRSquaredVanilla() : this.CalculateRSquared();
this.Mse = mse;
this.RSquared = r2;
if (weightFunc != null)
{
this.DiagnosePoints(weightFunc);
}
else
{
this.DiagnosePoints(x => 1);
}
this.state = FitlineState.DiagnosticsComplete;
}
else
{
throw new Exception("Has to complete model first, cannot diagnose regression");
}
}
