Bug report #14312

Processing: SAGA Raster statistics for polygons returns wrong values

Added by Paolo Cavallini about 4 years ago. Updated about 4 years ago.

Status:Closed
Priority:Normal
Assignee:Giovanni Manghi
Category:Processing/SAGA
Affected QGIS version:master Regression?:No
Operating System: Easy fix?:No
Pull Request or Patch supplied:No Resolution:fixed/implemented
Crashes QGIS or corrupts data:No Copied to github as #:22302

Description

Running example from:

https://github.com/qgis/QGIS-Documentation/blob/master/source/docs/training_manual/processing/geomorpho.rst

Raster statistics for polygons:
processing.runalg("saga:gridstatisticsforpolygons","/tmp/processing543c8fb958c34d0a8b161fc7f40b98d0/62593922b4bf47c186075beae8a72e8f/RESULT.sdat","/home/paolo/Scrivania/corso_analisi/QGIS_data/processing/more_backends/municipalities.shp",True,True,True,True,True,True,True,True,0,None)

returns wrong values. Zonal statistics from QGIS backend, on the same data, returns correct ones.
Unclear whether it's a saga or processing bug. Previous versions worked smoothly.

History

#1 Updated by Alexander Bruy about 4 years ago

Is running SAGA from commandline produce correct results?

#2 Updated by Paolo Cavallini about 4 years ago

  • Status changed from Open to Rejected
  • Resolution set to up/downstream

You are right, upstream problem, presumably related to incorrect handling of NULLs. Sorry for the noise.

#3 Updated by Paolo Cavallini about 4 years ago

  • Status changed from Rejected to Reopened
  • Tag set to easy

-METHOD=0 does indeed not disregard NoData cells.
As a workaround we could use -METHOD=1.
So it can be fixed on our side after all.

#4 Updated by Alexander Bruy about 4 years ago

Which SAGA version do you use, 2.2.3?

#5 Updated by Paolo Cavallini about 4 years ago

Exactly

#6 Updated by Giovanni Manghi about 4 years ago

  • Assignee changed from Victor Olaya to Giovanni Manghi

#7 Updated by Giovanni Manghi about 4 years ago

  • Resolution deleted (up/downstream)

#8 Updated by Giovanni Manghi about 4 years ago

  • Status changed from Reopened to In Progress
  • % Done changed from 0 to 100

#9 Updated by Giovanni Manghi about 4 years ago

  • Resolution set to fixed/implemented
  • Status changed from In Progress to Closed

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