Find nearest points of latitude and longitude from different data sets with different length

Question

I have two data set of different stations. The data are basically data.frames with coordinates, longitudes and latitudes. Given the first data set (or vice versa), I want to

Answer 1

The function s2_closest_feature() from the s2 package finds nearest points from different data sets.

For example, with your data:

library(s2)
set1_s2 <- s2_lnglat(set1$lon, set1$lat)
set2_s2 <- s2_lnglat(set2$lon, set2$lat)
set1$closest <- s2_closest_feature(set1_s2, set2_s2)
set1
#>         lon      lat closest
#> 1  13.67111 48.39167      10
#> 2  12.86695 48.14806      10
#> 3  15.94223 48.72111      10
#> 4  11.09974 47.18917       1
#> 5  12.95834 47.05444       1
#> 6  14.20389 47.12917       1
#> 7  11.86389 47.30667       1
#> 8  16.52667 47.84000       1
#> 9  16.19306 47.30417       1
#> 10 17.07139 48.10944       1