private double ArcLength(GeoLocation locationA, GeoLocation locationB, FormulaType formula)
{
switch (formula)
{
case FormulaType.SphericalLawOfCosinesFormula:
return ArcLengthSphericalLawOfCosines(locationA, locationB);
case FormulaType.HaversineFormula:
return ArcLengthHaversineFormula(locationA, locationB);
case FormulaType.VincentyFormula:
return ArcLengthVincentyFormula(locationA, locationB);
default:
return 0;
}
}
private double ArcLengthVincentyFormula(GeoLocation locationA, GeoLocation locationB)
{
return Math.Atan(Math.Sqrt(((Math.Pow(Math.Cos(locationB.LatitudeRad) * Math.Sin(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad)), 2)) + (Math.Pow((Math.Cos(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) - (Math.Sin(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad))), 2))) / ((Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) + (Math.Cos(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad))))));
}
private double ArcLengthSphericalLawOfCosines(GeoLocation locationA, GeoLocation locationB)
{
return Math.Acos((Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) + (Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad))));
}
private double ArcLengthHaversineFormula(GeoLocation locationA, GeoLocation locationB)
{
return 2 * Math.Asin(Math.Sqrt((Helpers.Sin2(Helpers.Diff(locationA.LatitudeRad, locationB.LatitudeRad) / 2)) + (Math.Cos(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Helpers.Sin2(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad) / 2))));
}
public double OrthodromicDistance(GeoLocation locationA, GeoLocation locationB, FormulaType formula)
{
return (c_AverageRadiusForSphericalApproximationOfEarth * ArcLength(locationA, locationB, formula));
}
private double ArcLengthVincentyFormula(GeoLocation locationA, GeoLocation locationB)
{
return(Math.Atan(Math.Sqrt(((Math.Pow(Math.Cos(locationB.LatitudeRad) * Math.Sin(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad)), 2)) + (Math.Pow((Math.Cos(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) - (Math.Sin(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad))), 2))) / ((Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) + (Math.Cos(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad)))))));
}
private double ArcLengthHaversineFormula(GeoLocation locationA, GeoLocation locationB)
{
return(2 * Math.Asin(Math.Sqrt((Helpers.Sin2(Helpers.Diff(locationA.LatitudeRad, locationB.LatitudeRad) / 2)) + (Math.Cos(locationA.LatitudeRad) * Math.Cos(locationB.LatitudeRad) * Helpers.Sin2(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad) / 2)))));
}
private double ArcLengthSphericalLawOfCosines(GeoLocation locationA, GeoLocation locationB)
{
return(Math.Acos((Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad)) + (Math.Sin(locationA.LatitudeRad) * Math.Sin(locationB.LatitudeRad) * Math.Cos(Helpers.Diff(locationA.LongitudeRad, locationB.LongitudeRad)))));
}
public double OrthodromicDistance(GeoLocation locationA, GeoLocation locationB, FormulaType formula)
{
return(c_AverageRadiusForSphericalApproximationOfEarth * ArcLength(locationA, locationB, formula));
}
