VBA哈斯汀配方

Question

我正在尝试将Haversine公式实现为excel函数。它看起来像这样：

Public Function Haversine(Lat1 As Variant, Lon1 As Variant, Lat2 As Variant, Lon2 As Variant)
Dim R As Integer, dlon As Variant, dlat As Variant, Rad1 As Variant
Dim a As Variant, c As Variant, d As Variant, Rad2 As Variant

R = 6371
dlon = Excel.WorksheetFunction.Radians(Lon2 - Lon1)
dlat = Excel.WorksheetFunction.Radians(Lat2 - Lat1)
Rad1 = Excel.WorksheetFunction.Radians(Lat1)
Rad2 = Excel.WorksheetFunction.Radians(Lat2)
a = Sin(dlat / 2) * Sin(dlat / 2) + Cos(Rad1) * Cos(Rad2) * Sin(dlon / 2) * Sin(dlon / 2)
c = 2 * Excel.WorksheetFunction.Atan2(Sqr(a), Sqr(1 - a))
d = R * c
Haversine = d
End Function

但是当我测试它时，我的距离越来越远...我不明白为什么。对于本主题中使用的坐标：Function to calculate distance between two coordinates shows wrong 我输出20013,44。谁知道这里有什么问题？找不到我的错误......

Answer 1

与JavaScript相比，Atan2在Excel中被定义为前置，即Atan2（x，y），而不是Atan2（y，x）。

您需要颠倒两个参数的顺序： -

c = 2 * Excel.WorksheetFunction.Atan2(Sqr(1 - a), Sqr(a))

请参阅this

所以

=haversine(59.3293371,13.4877472,59.3225525,13.4619422)

给出

1.65 km

这是乌鸦飞行时的正确距离。

Answer 2

很棒的工具！只是强调结果将以公里为单位，因此，如果您想英里将结果乘以0.62137。