Hi S�ren,
I would attack this problem in this way:
1. Make sure you have a column with a unique ID for each of your points.
2. Make a copy of your points table
3. Open the PointsCopy table (I'll call it this from now on) and add a
NumPoints
column to this table (type Integer)
4. Update the PointsCopy table like this using the MapBasic window:
Update PointsCopy Set OBJ = Buffer(OBJ, 12, 50 , "m")
Now your PointsCopy table contains buffer/circles with a radius of 50
meters.
5. Using Update Column you can now calculate the number of points in the
Points table
within each buffer.
Update Column
Table to Update: PointsCopy
Column To Update: NumPoints
Get values from: Points
Value: Count
Join: Where PointsCopy objects contains Points Objects
Now you have calculated how many points there is within each of these
buffers. Now
you just need to select those with more than 1.
6. Select * From Points Where ID In (Select ID From PointsCopy where
NumPoints > 1)
HTH,
Peter
------------------------------------------------------------------------------------------------
Peter Horsb�ll M�ller, GIS Udviklingskonsulent / GIS-Developer
Kampsax A/S - GIS Software & Solutions
Rugaardsvej 55, 5000 Odense, DK
tel: +45 6313 5013, dir:+45 6313 5008, fax: +45 6313 5090
mailto:[EMAIL PROTECTED]
www.kampsax-gis.dk and www.kampsax.dk
Authorized MapInfo Partner & Distributor in Denmark and Norway.
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----- Videresendt af Peter M�ller/Kampsax - 14-08-2002 12:29 -----
S�ren Lindqvist
<soren.lindqvist@ Til:
<[EMAIL PROTECTED]>
telia.com> cc:
Vedr.: MI-L Distance in point table
14-08-2002 09:48
Hello, I have a point table with customers and need to select thoose
customers that are within let say 50 meters of each other.
How should I write to select and be able save to a new table.
Can you do it with an SQL question? If you can how should it look like?
Using swedish projection RT90 2,5
Thanks
Soren
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