[GRASSLIST:5919] Re: strange d.histogram mess-up and a question

[Eric G. Miller]

On Sun, Mar 30, 2003 at 09:26:12AM -0500, Andrew wrote:
> I have a strange problem and I was wondering if someone might have an
> insight...

> Symptoms: Invoke d.histogram with a selected monitor window set to the
> approriate region and STDOUT echoes
> "r.stats: nn%" where nn is the incremented percentage complete. When r.stats
> reaches 100% the next line reads "segmentation fault" and nothing is
> displayed in the monitor window.

Try attached get_stats.c file 

  cd src/display/d.histogram/cmd
  mv get_stats.c get_stats.c.bak
  <save> get_stats.c 
  gmake5 -i

I found a couple potential trouble spots, but I have no idea if they are
related to your problem.


> #################################################
> ##################################################
> 
> Unrelated question: What rules are applied to set the defaultcolor palette
> to a raster image? I would like to know if the yellow->blue->red palette set
> by default uses percentage of full scale, standard deviations or some other
> approach to setting the color scale.

Generally the rules are linear min<->max.  grey.eq is histogram
equalized.  If no color rules exist, the rainbow palette is used.

-- 
echo ">gra.fcw at 2ztr< eryyvZ .T pveR" | rot13 | reverse
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