Ln (natural logarithm) button in Raster Calculator

[qgib]

Author Name: Mark Cresswell (Mark Cresswell)
Original Redmine Issue: 12030

Redmine category:raster_calculator

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It would be great if an 'Ln' logarithm function was available in the Raster Calculator. This would allow temperature and other geophysical parameters to be calculated from thermal radiance bands. The plugin 'RasterCalc' solved this for older versions of QGIS, but is not compatible with the current release.

[qgib]

Author Name: George Rodrigues da Cunha Silva (George Rodrigues da Cunha Silva)

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This is true. I'm developing a plugin that obviously depends on such calculation.

For what I can see in the repository, it seems simple to implement, but I do not have c++ skills or the environment to properly rig everything and do all the testing.

These are the supported nodes:

https://github.com/qgis/QGIS/blob/release-2_8/src/analysis/raster/qgsrastercalcnode.h#L38

We should support log and logn.

This is where the magic happens:

https://github.com/qgis/QGIS/blob/release-2_8/src/analysis/raster/qgsrastermatrix.cpp

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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implemented in 7019db8

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• resolution was changed from to fixed/implemented
• fixed_version_id removed Future Release - High Priority
• status_id was changed from Open to Closed