我试图找出第一条记录与按ID1分组的组的其余3条记录之间的距离。
例如(33.6008949,-83.83803)和(33.604248,-83.86729)之间的距离; (33.6008949,-83.83803)和(33.60586,-83.8711)之间的距离和
(33.6008949,-83.83803)和(33.6043777,-83.86624)之间的距离。
Row Id1 Id2 StartTime StopTime Latitude Longitude DateTime
1 71 34 2016-11-21 00:41:05 UTC 2016-11-21 00:47:06 UTC 33.6008949 -83.83803 2016-11-21 00:43:42 UTC
2 71 44 2016-11-21 00:54:55 UTC 2016-11-21 00:56:28 UTC 33.604248 -83.86729 2016-11-21 00:55:18 UTC
3 71 45 2016-11-21 02:08:17 UTC 2016-11-21 02:09:52 UTC 33.60586 -83.8711 2016-11-21 02:09:03 UTC
4 71 67 2016-11-21 02:16:02 UTC 2016-11-21 02:17:21 UTC 33.6043777 -83.86624 2016-11-21 02:16:28 UTC
为了计算点之间的距离,我使用以下函数:
from math import radians, cos, sin, asin, sqrt
def haversine(lon1, lat1, lon2, lat2):
lon1, lat1, lon2, lat2 = map(radians, [lon1, lat1, lon2, lat2])
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
c = 2 * asin(sqrt(a))
km = 6367 * c
return km
最佳答案
试试下面
#standardSQL
CREATE TEMPORARY FUNCTION distance(lat1 FLOAT64, lon1 FLOAT64, lat2 FLOAT64, lon2 FLOAT64)
RETURNS FLOAT64 AS ((
WITH constants AS (
SELECT 0.017453292519943295 AS p
)
SELECT 12742 * ASIN(SQRT(
0.5 - COS((lat2 - lat1) * p)/2 +
COS(lat1 * p) * COS(lat2 * p) *
(1 - COS((lon2 - lon1) * p))/2))
FROM constants
));
WITH YourTable AS (
SELECT 1 AS Row, 71 AS Id1, 34 AS Id2, '2016-11-21 00:41:05 UTC' AS StartTime, '2016-11-21 00:47:06 UTC' AS StopTime, 33.6008949 AS Latitude, -83.83803 AS Longitude, '2016-11-21 00:43:42 UTC' AS DateTime UNION ALL
SELECT 2 AS Row, 71 AS Id1, 44 AS Id2, '2016-11-21 00:54:55 UTC' AS StartTime, '2016-11-21 00:56:28 UTC' AS StopTime, 33.604248 AS Latitude, -83.86729 AS Longitude, '2016-11-21 00:55:18 UTC' AS DateTime UNION ALL
SELECT 3 AS Row, 71 AS Id1, 45 AS Id2, '2016-11-21 02:08:17 UTC' AS StartTime, '2016-11-21 02:09:52 UTC' AS StopTime, 33.60586 AS Latitude, -83.8711 AS Longitude, '2016-11-21 02:09:03 UTC' AS DateTime UNION ALL
SELECT 4 AS Row, 71 AS Id1, 67 AS Id2, '2016-11-21 02:16:02 UTC' AS StartTime, '2016-11-21 02:17:21 UTC' AS StopTime, 33.6043777 AS Latitude, -83.86624 AS Longitude, '2016-11-21 02:16:28 UTC' AS DateTime
)
SELECT *,
distance(Latitude, Longitude, FIRST_VALUE(Latitude) OVER(PARTITION BY Id1 ORDER BY Id2), FIRST_VALUE(Longitude) OVER(PARTITION BY Id1 ORDER BY Id2)) AS dist
FROM YourTable
ORDER BY Id1, Id2