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It could be user error, but for some reason, the reclass tool is just hanging and hanging...

QGIS 1.8 Compiled against GDAL/OGR 1.9.2 Ubuntu 12.04.1

  • Running the tool from the Sextante toolbox
  • Input is a 10' cellsize raster ~10mi x 10mi in area
  • grass region cellsize = 10
  • Reclass file is in order from what I can gather from the help

When run: - There is no process operating in the system monitor - Dialogue hangs and cursor shows progress spinny thing...

Not sure what else to say?

Does the GRASS tool run from this dialogue on a .tif? Or does it have to be run from the GRASS tools specifically?


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Can you try to run the reclass in GRASS directly, and report back? You will have to import the raster into GRASS. GRASS modules do not work on external formats. – Micha Feb 9 '13 at 19:49
Ok I got the reclass tool to work in GRASS directly - and it works really well, actually (love that I can have the reclass text file open while I have the tool open too - just so I can 'tweak' the reclass, then run the tool to see the update!) I'm going to try to run the tool again now that I have a GRASS dataset put together... – DPSSpatial Feb 11 '13 at 15:24
r.reclass only takes as input integer values (there's a reason for it),and to do it cast the value to int type. if you want to reclassify (values from x to y should be z) use r.recode – nickves May 10 '13 at 20:23

Sextante is still in active development and most likely there are a lot of bugs that occur in certain situations and on different systems.

In the meantime try to use the SAGA sextante toolset. It also has a reclass tool called "Reclassify Grid Values" in the "Grid - Tools" toolbox.

And don't forget to submit a bug to the qgis development team.

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You can report it here: (r.reclass takes just nanoseconds since it internally only generates a lookup table!). – markusN Feb 9 '13 at 9:27
up vote 0 down vote accepted

Running reclass in GRASS directly solved the problem thanks to @Micha for the response.

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