如何计算两个GPS坐标之间的距离(使用经纬度)?
当前回答
Unity版本c#
Haversine Algorithm。
public float Distance(float lat1, float lon1, float lat2, float lon2)
{
var earthRadiusKm = 6371;
var dLat = (lat2 - lat1) * Mathf.Rad2Deg;
var dLon = (lon2 - lon1) * Mathf.Rad2Deg;
var a = Mathf.Sin(dLat / 2) * Mathf.Sin(dLat / 2) +
Mathf.Sin(dLon / 2) * Mathf.Sin(dLon / 2) *
Mathf.Cos(lat1 * Mathf.Rad2Deg) * Mathf.Cos(lat2 * Mathf.Rad2Deg);
var c = 2 * Mathf.Atan2(Mathf.Sqrt(a), Mathf.Sqrt(1 - a));
return earthRadiusKm * c;
}
其他回答
这取决于你需要它有多准确。如果你需要精确到毫米的精度,最好看看使用椭球的算法,而不是球体,比如Vincenty的算法。
一个T-SQL函数,我用来根据中心的距离选择记录
Create Function [dbo].[DistanceInMiles]
( @fromLatitude float ,
@fromLongitude float ,
@toLatitude float,
@toLongitude float
)
returns float
AS
BEGIN
declare @distance float
select @distance = cast((3963 * ACOS(round(COS(RADIANS(90-@fromLatitude))*COS(RADIANS(90-@toLatitude))+
SIN(RADIANS(90-@fromLatitude))*SIN(RADIANS(90-@toLatitude))*COS(RADIANS(@fromLongitude-@toLongitude)),15))
)as float)
return round(@distance,1)
END
下面是c#语言(用纬度和弧度表示):
double CalculateGreatCircleDistance(double lat1, double long1, double lat2, double long2, double radius)
{
return radius * Math.Acos(
Math.Sin(lat1) * Math.Sin(lat2)
+ Math.Cos(lat1) * Math.Cos(lat2) * Math.Cos(long2 - long1));
}
如果你的纬度和长度是用角度表示的,那么除以180/PI就可以转换成弧度。
你可以在f#的fssnip中找到这个实现(有一些很好的解释)
以下是重要的部分:
let GreatCircleDistance<[<Measure>] 'u> (R : float<'u>) (p1 : Location) (p2 : Location) =
let degToRad (x : float<deg>) = System.Math.PI * x / 180.0<deg/rad>
let sq x = x * x
// take the sin of the half and square the result
let sinSqHf (a : float<rad>) = (System.Math.Sin >> sq) (a / 2.0<rad>)
let cos (a : float<deg>) = System.Math.Cos (degToRad a / 1.0<rad>)
let dLat = (p2.Latitude - p1.Latitude) |> degToRad
let dLon = (p2.Longitude - p1.Longitude) |> degToRad
let a = sinSqHf dLat + cos p1.Latitude * cos p2.Latitude * sinSqHf dLon
let c = 2.0 * System.Math.Atan2(System.Math.Sqrt(a), System.Math.Sqrt(1.0-a))
R * c
这是“Henry Vilinskiy”为MySQL和km改编的版本:
CREATE FUNCTION `CalculateDistanceInKm`(
fromLatitude float,
fromLongitude float,
toLatitude float,
toLongitude float
) RETURNS float
BEGIN
declare distance float;
select
6367 * ACOS(
round(
COS(RADIANS(90-fromLatitude)) *
COS(RADIANS(90-toLatitude)) +
SIN(RADIANS(90-fromLatitude)) *
SIN(RADIANS(90-toLatitude)) *
COS(RADIANS(fromLongitude-toLongitude))
,15)
)
into distance;
return round(distance,3);
END;