[GRASS-dev] [GRASS GIS] #2902: i.segment.hierarchical: Execution of subprocesses was not successful

[GRASS GIS]

#2902: i.segment.hierarchical: Execution of subprocesses was not successful
-------------------------+-------------------------------------------------
  Reporter:  mlennert    |      Owner:  grass-dev@…
      Type:  defect      |     Status:  new
  Priority:  normal      |  Milestone:  7.0.5
 Component:  Addons      |    Version:  svn-trunk
Resolution:              |   Keywords:  i.segment.hierarchical GridModule
       CPU:              |  subprocesses
  Unspecified            |   Platform:  Unspecified
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Comment (by mlennert):

 Replying to [comment:7 mlennert]:
 > Replying to [comment:5 mlennert]:
 > > The first error was solved, but now I get a new error (same message)
 at the very end of an attempt to segment a fairly large image (400 mio
 pixels), i.e. after the patching of all tiles. Unfortunately, I do not get
 the error when setting the debug parameter, so I cannot see what exactly
 is the issue.
 > >
 >
 > I got a more concrete message:
 >
 > {{{
 > Start patching the segments
 > Traceback (most recent call last):
 >   File "/home/mlennert/.grass7/addons/scripts/i.segment.hierarchical",
 line 254, in <module>
 >     SEG.run()
 >   File "/data/home/mlennert/SRC/GRASS/grass_trunk/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/grid/grid.py", line 567, in run
 >     self.patch()
 >   File "/home/mlennert/.grass7/addons/scripts/i.segment.hierarchical",
 line 182, in patch
 >     self.start_row, self.start_col, self.out_prefix)
 >   File
 "/home/mlennert/.grass7/addons/etc/i.segment.hierarchical/isegpatch.py",
 line 46, in rpatch_map
 >     rrasts[-1].open('r')
 >   File "/data/home/mlennert/SRC/GRASS/grass_trunk/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/raster/__init__.py", line 210, in open
 >     raise OpenError(str_err)
 > grass.exceptions.OpenError: La carte n'existe pas, impossible de
 l'ouvrir en mode 'r'
 > }}}
 >
 > Sorry for the French. In English it is: "The map does not exist, I can't
 open in 'r' mode"
 >
 > As indicated, this comes from the open() function of the RasterRow class
 in lib/python/pygrass/raster/__init__.py, which is called in the
 iseg_patch.py file of i.segment.hierarchical:
 >
 > {{{
 >         for col in range(len(rbbox)):
 >             msgr.percent(row, nrows, 1)
 >             rrasts.append(RasterRow(name=raster,
 >                                     mapset=mset_str % (start_row + row,
 >                                                        start_col +
 col)))
 >             rrasts[-1].open('r')
 > }}}
 >
 > At this stage, I don't really understand which file it is and why it
 doesn't exist...

 Just pure speculation at this point: As this error arrives only when
 working on a large region, which means that if tiles are small, there are
 many tiles, could it be that rrasts becomes too big ?

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Ticket URL: <https://trac.osgeo.org/grass/ticket/2902#comment:9>
GRASS GIS <https://grass.osgeo.org>