Bug report #18006

Geoprocessing Tools Fail with Memory Layers in QGIS 2.18

Added by Calvin Hamilton almost 3 years ago. Updated almost 3 years ago.

Status:Rejected
Priority:Normal
Assignee:-
Category:Vectors
Affected QGIS version:2.18.16 Regression?:Yes
Operating System:Windows Easy fix?:No
Pull Request or Patch supplied:No Resolution:duplicate
Crashes QGIS or corrupts data:Yes Copied to github as #:25902

Description

I have attached a python script to illustrate this bug. I posted this problem on the qgis-developer group and Richard Duivenvoorde confirmed the problem. This problem appears to only affect QGIS 2.18.x. Richard tested it on QGIS 3.0 and it works fine. example1.jpg and exmple2.jpg were run using 2.14 to show the correct results.

Run two-polygons.py and it will create two polygons (see example1.jpg). Note that I have given Polygon 2 some transparency so you can see how they overlap. Now run "Vector->Geoprocessing Tools->Clip". I used 'Polygon 1' for the 'Input vector layer' and 'Polygon 2' for the 'Clip layer'. QGIS 2.14 produces the correct results as shown by example2.jpg. QGIS 2.18.16 does not clip. It returns 'Polygon 1' as shown by qgis2.18example.jpg.

This example just shows the Clip function but I think all of the Geoprocessing Tools have issues. 'Intersection' gives the same results. 'Symmetrical difference' and 'Difference' don't return any polygon result, but they should both return a result. I have not checked the rest.

two-polygons.py Magnifier - Script to illustrate problem (912 Bytes) Calvin Hamilton, 2018-01-30 08:37 PM

example1.jpg - Polygons created by the script (93.3 KB) Calvin Hamilton, 2018-01-30 08:44 PM

example2.jpg - Correct results showing clip function (94.6 KB) Calvin Hamilton, 2018-01-30 08:44 PM

qgis2.18example.jpg - Error results of clip function (106 KB) Calvin Hamilton, 2018-01-30 08:53 PM


Related issues

Related to QGIS Application - Bug report #16524: Processing/geoprocessing operations failing in 2.18 with ... Closed 2017-05-05

History

#1 Updated by Alexander Bruy almost 3 years ago

  • Resolution set to duplicate
  • Status changed from Open to Rejected

Duplicates #16524

#2 Updated by Alexander Bruy almost 3 years ago

  • Related to Bug report #16524: Processing/geoprocessing operations failing in 2.18 with memory layers added

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