Incorrect Python ver. with GDAL Merge tool in QGIS 3

[qgib]

Author Name: Joe Krienert (Joe Krienert)
Original Redmine Issue: 18413
Affected QGIS version: 3.0.0
Redmine category:processing/gdal
Assignee: Joe Krienert

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Used OSGeo4W64 installer for QGIS 3 and friends. Made sure GDAL libs were included.
When running GDAL Merge tool an error is raised similar to #17298
Adding...

python --version

... to the gdal_merge.bat indicates it is trying to use 2.7.5.

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Related issue(s): #25196 (duplicates)
Redmine related issue(s): 17298

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[qgib]

Author Name: Joe Krienert (Joe Krienert)

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Error output:

2018-03-11T19:56:08	INFO	cmd.exe /C  gdal_merge.bat -pct -ot Float32 -of GTiff -o "C:/Users/Joe M. Krienert/Desktop/Output.tif" C:/Users/Joe M. Krienert/Desktop/ned03m37089a1.tif C:/Users/Joe M. Krienert/Desktop/ned03m37089b2.tif
2018-03-11T19:56:08	INFO	GDAL execution console output
            Python 2.7.5
			File "C:\OSGEO4~1\apps\Python36\lib\site.py", line 177
			      file=sys.stderr)
			        ^
			SyntaxError: invalid syntax

[qgib]

Author Name: Giovanni Manghi (@gioman)

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So the error does not seems related to the python version, right?

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• category_id was changed from GDAL Tools to Processing/GDAL
• status_id was changed from Open to Feedback
• regression was changed from 0 to 1

[qgib]

Author Name: Joe Krienert (Joe Krienert)

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Should GDAL be using Python version 3.6 in QGIS 3? If so, then the Python version might be the problem. If not, then there might be something astray in the basic OSGeo4W64 installer?

[qgib]

Author Name: Giovanni Manghi (@gioman)

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Joe Krienert wrote:

Should GDAL be using Python version 3.6 in QGIS 3? If so, then the Python version might be the problem. If not, then there might be something astray in the basic OSGeo4W64 installer?

yes, qgis 3 uses python 3.

[qgib]

Author Name: Joe Krienert (Joe Krienert)

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When opening the Python terminal plugin in QGIS 3 desktop and import/calling print (sys.version), the ver. stated is Python 3.
Could the GDAL merge error be associated with conflicting syntax of attempting to run Python 3 commands in a Python 2.7 environment?

[qgib]

Author Name: Joe Krienert (Joe Krienert)

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Python 2.7.5
File "C:\OSGEO4~1\apps\Python36\lib\site.py", line 177
      file=sys.stderr)
       ^
      Syntax Error: invalid syntax

Does this code snippet from the GDAL merge tool log suggest a conflict between the library (Python36) and active Python version (2.7.5)?

Seems anomolous that the Python plugin terminal tells Python 3 as the active version, but the processing tool call to GDAL states ver 2.7.5.

Does GDAL not support Python 3?

[qgib]

Author Name: Joe Krienert (Joe Krienert)

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This test suggest that GDAL is switching the active python version from v. 3.6 to 2.7.

From a freshly opened (as admin) OSGeo4W shell...

Check the current ver. of Python in use:

C:\Windows\System32>python --version
Python 2.7.5

Oddly set to ver. 2.7.5, update to ver. 3 environment:

C:\Windows\System32>gdal-dev-py3-env
C:\Windows\System32>call gdal-dev-env.bat
C:\Windows\System32>SET GDAL_DATA=C:\OSGEO4~1\apps\gdal-dev\share\gdal
C:\Windows\System32>SET GDAL_DRIVER_PATH=C:\OSGEO4~1\apps\gdal-dev\bin\gdalplugins
C:\Windows\System32>PATH C:\OSGEO4~1\apps\gdal-dev\bin;C:\OSGEO4~1\apps\Python36\Scripts;C:\OSGEO4~1\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32\WBem;C:\OSGEO4~1\apps\msys\bin
C:\Windows\System32>call py3_env.bat
C:\Windows\System32>SET PYTHONPATH=
C:\Windows\System32>SET PYTHONHOME=C:\OSGEO4~1\apps\Python36
C:\Windows\System32>PATH C:\OSGEO4~1\apps\Python36;C:\OSGEO4~1\apps\Python36\Scripts;C:\OSGEO4~1\apps\gdal-dev\bin;C:\OSGEO4~1\apps\Python36\Scripts;C:\OSGEO4~1\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32\WBem;C:\OSGEO4~1\apps\msys\bin
C:\Windows\System32>SET PYTHONPATH=C:\OSGEO4~1\apps\gdal-dev\pymod3\lib\site-packages;
C:\Windows\System32>PATH C:\OSGEO4~1\apps\gdal-dev\pymod3\scripts;C:\OSGEO4~1\apps\Python36;C:\OSGEO4~1\apps\Python36\Scripts;C:\OSGEO4~1\apps\gdal-dev\bin;C:\OSGEO4~1\apps\Python36\Scripts;C:\OSGEO4~1\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32\WBem;C:\OSGEO4~1\apps\msys\bin

Verify environment ver. changed:

C:\Windows\System32>python --version
Python 3.6.0

Attempt GDAL merge:

C:\Windows\System32>gdal_merge.bat -pct -ot Float32 -of GTiff -o "C:/Users/Joe/Desktop/OUTPUT.tif" D:/Personal/ned03m37089a1.tif D:/Personal/ned03m37089a2.tif
  File "C:\OSGEO4~1\apps\Python36\lib\site.py", line 177
    file=sys.stderr)
        ^
SyntaxError: invalid syntax

Double check Python environment ver:

C:\Windows\System32>python --version
Python 2.7.5

Why would calling GDAL merge reset the python environment ver?

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• description was changed from Used OSGeo4W64 installer for QGIS 3 and friends. Made sure GDAL libs were included.
  When running GDAL Merge tool an error is raised similar to issue "Processing: gdal merge python error on QGIS 3 #25196.":https://issues.qgis.org/issues/17298
  Adding...

python --version

... to the gdal_merge.bat indicates it is trying to use 2.7.5. to Used OSGeo4W64 installer for QGIS 3 and friends. Made sure GDAL libs were included.
When running GDAL Merge tool an error is raised similar to #25196
Adding...

python --version

... to the gdal_merge.bat indicates it is trying to use 2.7.5.

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• duplicates was configured as Processing: gdal merge python error on QGIS 3 #25196

[qgib]

Author Name: Nyall Dawson (@nyalldawson)

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This was fixed upstream in osgeo4w

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• resolution was changed from to up/downstream
• status_id was changed from Feedback to Closed