public Tile deg2Num(double lon, double lat, double zoom)
        {
            Tile   tile    = new Tile();
            double lat_rad = lat / 180 * Math.PI;
            double lon_rad = lon / 180 * Math.PI;
            double n       = Math.Pow(double.Parse("2"), zoom);

            tile.tileX = Convert.ToInt32(((lon + 180.0) / 360.0 * n));
            tile.tileY = Convert.ToInt32((1.0 - Trig.Asinh(Trig.Tan(lat_rad)) / Constants.Pi) / 2.0 * n);
            return(tile);
        }
        public void CanComputeInverseHyperbolicSine(double value, double expected)
        {
            var actual = Trig.Asinh(value);

            AssertHelpers.AlmostEqual(expected, actual, 14);
        }