/// <summary>
/// Checks if the computed value for isInCircle is correct, using
/// double-double precision arithmetic.
/// </summary>
/// <param name="a">A vertex of the triangle</param>
/// <param name="b">A vertex of the triangle</param>
/// <param name="c">A vertex of the triangle</param>
/// <param name="p">The point to test</param>
private static void CheckRobustInCircle(Coordinate a, Coordinate b, Coordinate c,
Coordinate p)
{
bool nonRobustInCircle = IsInCircle(a, b, c, p);
bool isInCircleDD = TriPredicate.IsInCircleDD(a, b, c, p);
bool isInCircleCC = TriPredicate.IsInCircleCC(a, b, c, p);
var circumCentre = Triangle.Circumcentre(a, b, c);
Console.WriteLine("p radius diff a = "
+ Math.Abs(p.Distance(circumCentre) - a.Distance(circumCentre))
/ a.Distance(circumCentre));
if (nonRobustInCircle != isInCircleDD || nonRobustInCircle != isInCircleCC)
{
Console.WriteLine("inCircle robustness failure (double result = "
+ nonRobustInCircle
+ ", DD result = " + isInCircleDD
+ ", CC result = " + isInCircleCC + ")");
Console.WriteLine(WKTWriter.ToLineString(new CoordinateArraySequence(
new Coordinate[] { a, b, c, p })));
Console.WriteLine("Circumcentre = " + WKTWriter.ToPoint(circumCentre)
+ " radius = " + a.Distance(circumCentre));
Console.WriteLine("p radius diff a = "
+ Math.Abs(p.Distance(circumCentre) / a.Distance(circumCentre) - 1));
Console.WriteLine("p radius diff b = "
+ Math.Abs(p.Distance(circumCentre) / b.Distance(circumCentre) - 1));
Console.WriteLine("p radius diff c = "
+ Math.Abs(p.Distance(circumCentre) / c.Distance(circumCentre) - 1));
Console.WriteLine();
}
}
public double runDDSelf2(int nIter)
{
Stopwatch sw = new Stopwatch();
sw.Start();
for (int i = 0; i < nIter; i++)
{
TriPredicate.IsInCircleDD3(_pa, _pb, _pc, _pp);
}
sw.Stop();
Console.WriteLine("DD-Self2: nIter = " + nIter
+ " time = " + sw.ElapsedMilliseconds);
return(sw.ElapsedMilliseconds / (double)nIter);
}