Hello,

My dataset has three columns. In column 1 I have county1 which is a set of a fixed number of counties ( 100) out of all the census counties. Column 3 is county2 which has all the counties from the census, unlike the county1 column. And, in column 2 I have the distance between the fixed number of counties in a column of county1 and all the counties from the census in county2.

My goal is to find the minimum distance of the unique county present in column 3 from any of the fixed counties in column 1.

Like in the 3rd and 4th line of data in the county2 column the county 10001 shows up twice and the minimum distance for that county is 30.357154190846018 from the county 10005 in the county1 column. County 12121 and 12125 also show up twice in county2 column.

I want my desired variable to show up that minimum distance for each unique county from the county2 column except for those counties which are present in county1 column ( 100 fixed counties in county1 column).

May I have some guidance how I can do it?

Code:
* Example generated by -dataex-. For more info, type help dataex
clear
input long county1 double mi_to_county long county2
10001 30.357154190846018 10005
10001  33.93271490946873 10003
10003  33.93271490946873 10001
10005 30.357154190846018 10001
12001  21.94139189527779 12007
12001 26.160991422024676 12125
12001 26.527847890310913 12041
12001  36.84643076250594 12019
12001  37.26131475453462 12075
12001  37.32388476194004 12107
12001  37.74940321571971 12083
12001  40.91842391588499 12023
12001 44.941311511693854 12003
12001  50.78094710678782 12029
12001  52.02776446747155 12121
12001  53.80338887869782 12067
12001  58.37400366291111 12017
12003  19.06133167684259 12125
12003 20.428353446347472 12023
12003  27.31084808096766 12007
12003  32.92368786810345 13049
12003  35.31646691638998 12019
12003  37.44802004706887 12089
12003 39.019664192183974 12031
12003  40.33782725115972 12047
12003  41.39883902283289 13101
12003  42.25346062002965 12121
12003 44.941311511693854 12001
12003  47.39732770502037 13065
12003  50.68954033379425 13299
12003  50.94956183265025 12041
12003  56.91760482788743 13039
end