haversine formula for lat long in csharp

main.cs
public static double Haversine(double lat1, double lon1, double lat2, double lon2, double radius = 6371)
{
    var dLat = ToRadians(lat2 - lat1);
    var dLon = ToRadians(lon2 - lon1);
    var a = Math.Sin(dLat / 2) * Math.Sin(dLat / 2) + Math.Cos(ToRadians(lat1)) 
            * Math.Cos(ToRadians(lat2)) * Math.Sin(dLon / 2) * Math.Sin(dLon / 2);
    var c = 2 * Math.Asin(Math.Min(1, Math.Sqrt(a)));
    return radius * c;
}

private static double ToRadians(double angle)
{
    return Math.PI * angle / 180.0;
}
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main.cs
double distance = Haversine(32.050382, 34.766149, 37.774929, -122.419416);
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