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I have a set of points and a set of lines. I'd like to know distances of the points from the closest line... answering the question "how many points are within 500m to 1000m of one of the lines, how many between 1000m to 2000m, etc."

Distances can be approximate if necessary (i.e. between 500m and 1km as a category) but if it's possible to do something more refined that would be great.

Data is currently in Mapinfo TAB files.

I seek a Mapinfo solution, if possible.

I have a working but very inefficient system just now which looks like this ... buffer the lines information, creating several files/tables, one for a buffer 500m from line (call this "buffer500m"), one for 1km (buffer1000m), one for 2km etc, then do simple repeated MapInfo SQL queries. With these I select all points within the wider buffer, save this (call this "pointswithin1000m" etc), then from these results again using an SQL select query select those in the narrower buffer and delete these... the result being a file/table with only those points in the wider buffer but not in the narrower one. This has to be repeated for each distance (i.e. once for 500m to 1km, once for 1km to 2km, and so on.

I tried a more sophisticated SQL select to give me those points within the wider buffer but not within the narrower buffer but either this wasn't possible or I didn't get the syntax right.

  • Currently I can add an answer, but I can give you one here for now and then add it as an answer later on: Have a look at the tool called Distance Calculator. It can calculate the distance from all your points to the nearest line – Peter Horsbøll Møller Apr 26 '14 at 9:54
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    Thank you. I see what looks like good information here (info from Pitney Bowes) which I'll pursue. – Rostranimin Apr 26 '14 at 10:17

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