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How could I create a buffer for each set of points (colour group) separately and in one procedure in QGIS 3?

The image below shows a subset of points for buffering.

Points for buffering

PolyGeo
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Bruce T.
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1 Answers1

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In your Attribute Table, you need to create (unless you already have it) a field which will define the unique buffer distance for each of your points.

Then you will be able to accomplish the buffering process by applying

Vector > Geoprocessing Tool > Variable distance buffer

Elongation:

  • If I have correctly understood the question gist, you are able to execute buffering "separately" by choosing the "Selected features only" in the "Variable distance buffer". Those selected features can be achieved beforehand through the basic "Selection by Expression".
  • Be careful with units. The buffer size is always applied in the layer CRS units.
  • There is an alternative way to accomplish this task with MMQGIS plugin.
  • Moreover, it is possible to apply v.buffer from GRASS GIS library.

A short practical example based on Airports data from Natural Earth.

In Attribute Table of the Airports layer, I will use an already created attribute "wdid_score" which is an integer type and looks like distance in meters. Example_of_the_attribute

Then (after CRS adjustment) I proceeded with Variable distance buffer. See image below. Variable_distance_buffer

References:

Taras
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  • Thanks Taras - I see, but needed to buffer each group separately using the same radius - found a response from @Kazuhito suggesting just to buffer all together then dissolve on attribute basis (Dissolve tool GDAL)..this worked! – Bruce T. Oct 09 '18 at 19:25
  • @Bruce T., can you please adjust your question in case if I misled the idea behind it. And by any means @Kazuhito deserves appreciation, however, it would be nicer if you @Bruce T. can embed his response into your question as a reference. Thanks – Taras Oct 09 '18 at 20:30