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In my vector layer I want to select points within a buffer of 12 meters and with an exception (if 'Name' is not "James" than select).

Is this possible with "select by expression"?

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Yes this is possible. You need to calculate the distance between every point and your reference point using the distance function (a buffer is a misleading idea), and add a second condition using the AND operator. This could give something like:

distance( geomFromWKT('POINT(4 4)') ,  $geometry ) <= 12 AND  "Name"  IS NOT 'James'

where $geometry are all the points, and geomFromWKT('POINT(4 4)') your reference point (in Well Known Text format). Make sure you get the single and double quotes right: double quotes are for field names and single quotes for strings.

  • Sorry, there is a mistake in my question. I want select points within a distance <= 12 meters and with the expression that the Name column is not the same. What mean is that I want to find points which are closer than 12m and they do not have the same attribute (Name). – Pimpel Sep 15 '15 at 14:46
  • Ok I see. What happens if there is more than 1 point within 12 meters? Could we say that what you want is select points that don't have any other point with the same attribute within a distance of 12 meters? – chkaiser Sep 15 '15 at 16:57
  • Not really. The points are placed in rows. Every row has it's own name. I want to know if there are points too close to the neighbour row. If the points of a row are closer than 12 meters...it doesn't matter. – Pimpel Sep 15 '15 at 18:14
  • @Pimpel if your question can be improved then please use its edit button to do that rather than in comments on an answer to it. – PolyGeo Mar 19 '16 at 2:06

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