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.Net計(jì)算方式
public static class CCalculationGPSCoordinateDistance
{
private const double dEARTH_RADIUS = 6378.137; // 地球半徑
private static double Rad(double d)
{
return (d * Math.PI / 180.0);
}
/// <summary>
/// 計(jì)算兩個(gè)坐標(biāo)的距離
/// </summary>
/// <param >第一個(gè)坐標(biāo)緯度</param>
/// <param >第一個(gè)坐標(biāo)經(jīng)度</param>
/// <param >第二個(gè)坐標(biāo)緯度</param>
/// <param >第二個(gè)坐標(biāo)經(jīng)度</param>
/// <returns>兩個(gè)坐標(biāo)間的距離</returns>
public static double GetDistance(double dLngPre, double dLatPre, double dLngNext, double dLatNext)
{
double dRadLatPre = Rad(dLatPre);
double dRadLatNext = Rad(dLatNext);
double a = dRadLatPre - dRadLatNext;
double b = Rad(dLngPre) - Rad(dLngNext);
double s = 2 * Math.Asin(Math.Sqrt(Math.Pow(Math.Sin(a / 2), 2) + Math.Cos(dRadLatPre) * Math.Cos(dRadLatNext) * Math.Pow(Math.Sin(b / 2), 2)));
s = s * dEARTH_RADIUS;
s = Math.Round(s * 10000) / 10000;
return s;
}
}
數(shù)據(jù)庫(kù)計(jì)算方法
DECLARE @dEarthRadius FLOAT -- 地球半徑
SET @dEarthRadius = 6378.137 -- 設(shè)置地球半徑
DECLARE @dLng FLOAT -- 上一條數(shù)據(jù)的緯度
DECLARE @dLat FLOAT -- 上一條數(shù)據(jù)的經(jīng)度
DECLARE @dTemLng FLOAT -- 當(dāng)前緯度
DECLARE @dTemLat FLOAT -- 當(dāng)前經(jīng)度
DECLARE @dTemA FLOAT -- 臨時(shí)變量A
DECLARE @dTemB FLOAT -- 臨時(shí)變量B
DECLARE @dMeters FLOAT -- 兩點(diǎn)間的距離(單位:米)
DECLARE @dTemPre FLOAT -- 臨時(shí)變量
DECLARE @dTemNext FLOAT -- 臨時(shí)變量
SET @dTemPre = (@dTemLat * PI() / 180.0)
SET @dTemNext = (@dLat * PI() / 180.0)
SET @dTemA = @dTemPre - @dTemNext
SET @dTemB = (@dTemLng * PI() / 180.0) - (@dLng * PI() / 180.0)
SET @dMeters = ROUND((2 * ASIN(SQRT(POWER(SIN(@dTemA / 2),2)
+COS(@dTemPre)* COS(@dTemNext) * POWER(SIN(@dTemB / 2),2)))) * @dEarthRadius,5) * 1000 -- 舍入精確度并把km裝換成m
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