private double Interpolate1D(PValue _pv)
{
if (_pv == null)
{
return(double.NaN);
}
PValue pv1, pv2;
this.FindNearestNeighbors(_pv, out pv1, out pv2);
// check the neighbors
bool neighb_not_same = PValue.InGeneralPosition1D(pv1, pv2);
if (neighb_not_same)
{
// interpolate
double f1, f2;
PValue.GetLinearCoords(pv1, pv2, _pv, out f1, out f2);
if (this.CanInterpolate)
{
return(f1 * this.table[pv1] + f2 * this.table[pv2]);
}
else
{
return((f1 > f2) ? this.table[pv1] : this.table[pv2]);
}
}
else
{
// the neighbors are the same -> we are out of bounds
return(this.table[pv1]);
}
}
public double this[PValue index]
{
get
{
if (!this.IsValid)
{
return(double.NaN);
}
if (this.table.ContainsKey(index))
{
return(this.table[index]);
}
else
{
return(this.RetrieveValue(index));
}
}
set
{
if (this.IsValid && this.table.ContainsKey(index))
{
this.table[index] = value;
}
}
}
private void FindNearestNeighbors(PValue _pv, out PValue _pvSmaller, out PValue _pvBigger, out PValue _pv3)
{
int n = this.table.Count;
int counter = -1;
foreach (var entry in this.table)
{
counter++;
if (entry.Key >= _pv)
{
break;
}
}
_pvSmaller = this.table.ElementAt(counter).Key;
if (counter == 0 || counter == n - 1)
{
// A. out of range
_pvBigger = this.table.ElementAt(counter).Key;
_pv3 = null;
return;
}
else
{
_pvBigger = this.table.ElementAt(counter + 1).Key;
}
// B. find a third point for an interpolation triangle
// order the table values according to distance from the query value _pv
SortedList <PValue, double> sorted_acc_to_dist = new SortedList <PValue, double>(new PValueDistComparer(_pv));
foreach (var entry in this.table)
{
if (entry.Key == _pvSmaller || entry.Key == _pvBigger)
{
continue;
}
sorted_acc_to_dist.Add(entry.Key, entry.Value);
}
// find closest value that builds a triangle around the query value _pv
foreach (var entry in sorted_acc_to_dist)
{
if (PValue.IsInsideTriangle(_pvSmaller, _pvBigger, entry.Key, _pv, true))
{
_pv3 = entry.Key;
return;
}
}
// C. no well-defined triangle could be found
// if none could be found, leave the third point empty
_pv3 = null;
}
private double RetrieveValue(PValue _pv)
{
if (_pv == null)
{
return(double.NaN);
}
if (_pv.Dim == ParameterValueDim.DIM_1)
{
return(this.Interpolate1D(_pv));
}
else if (_pv.Dim == ParameterValueDim.DIM_2)
{
return(this.Interpolate2D(_pv));
}
else
{
return(this.table.ElementAt(0).Value);
}
}
private double Interpolate2D(PValue _pv)
{
if (_pv == null)
{
return(double.NaN);
}
PValue pv1, pv2, pv3;
this.FindNearestNeighbors(_pv, out pv1, out pv2, out pv3);
// check the neighbors
if (pv3 == null)
{
// 1D interpolation
return(Interpolate1D(_pv));
}
else
{
// 2D interpolation
if (this.CanInterpolate)
{
double f1, f2, f3;
PValue.GetBarycentricCoords(pv1, pv2, pv3, _pv, out f1, out f2, out f3);
return(f1 * this.table[pv1] + f2 * this.table[pv2] + f3 * this.table[pv3]);
}
else
{
SortedList <PValue, double> sorted_neighb = new SortedList <PValue, double>(new PValueDistComparer(_pv));
sorted_neighb.Add(pv1, this.table[pv1]);
sorted_neighb.Add(pv2, this.table[pv2]);
sorted_neighb.Add(pv3, this.table[pv3]);
return(sorted_neighb.ElementAt(0).Value);
}
}
}
private void FindNearestNeighbors(PValue _pv, out PValue _pvSmaller, out PValue _pvBigger)
{
int n = this.table.Count;
int counter = -1;
foreach (var entry in this.table)
{
counter++;
if (entry.Key >= _pv)
{
break;
}
}
_pvSmaller = this.table.ElementAt(counter).Key;
if (counter == 0 || counter == n - 1)
{
_pvBigger = this.table.ElementAt(counter).Key;
}
else
{
_pvBigger = this.table.ElementAt(counter + 1).Key;
}
}