[GRASS-dev] [GRASS GIS] #2714: wish: logarithmic legend for raster maps

[GRASS GIS]

#2714: wish: logarithmic legend for raster maps
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  Reporter:  veroandreo   |      Owner:  grass-dev@…
      Type:  enhancement  |     Status:  new
  Priority:  normal       |  Milestone:  7.0.5
 Component:  Display      |    Version:  svn-releasebranch70
Resolution:               |   Keywords:  d.legend, gsoc2016, cartography
       CPU:  x86-64       |   Platform:  All
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Comment (by veroandreo):

 Replying to [comment:11 lazaa]:
 > Thanks for real data, it was much easier find the mistake. It gives
 better results now.

 Yes, it is better indeed. But check how the scale for chlorophyll proposed
 by NASA looks like (and how a logarithmic scale looks like in general):
 http://oceancolor.gsfc.nasa.gov/images/CHL_chlor_a_colorscale.png

 Values should be equally spaced, "graphically" speaking (for example:
 0.01, 0.03, 0.1, 0.3, 1.0, 3.0, 10.0) and therefore more space in the
 color palette is needed for lower values, i.e.: more space for "blues"
 "cyans" and "greens" in your example (there's still a lot of red).

 > ...
 >
 > but maybe I should add new option so user can determine how many digits
 display?

 This could be useful in general :)

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Ticket URL: <https://trac.osgeo.org/grass/ticket/2714#comment:13>
GRASS GIS <https://grass.osgeo.org>