Re: [ferret_users] Color error in shading with -gif

[Ge Peng - NOAA Affiliate <ge.peng@xxxxxxxx>]

Yes, shading plot twice appears to a work-around solution for the problem.

However, shifting color scales in the same figure with multiple plots can be disconcerting as it affects your analysis results and potentially impacts the scientific outcomes. As the result, I usually have to create each shading figure individually as well to see if there is color scale shift as shading the high-resolution fields twice may not be something one wants to do unless it is necessary.

It would be better if this issue can be dealt with by ferret.

Thanks,

--- Peng

-----------------------------------------------

Ge Peng, Ph.D

Research Scholar

Cooperative Institute for Climate and Satellites

North Caroline State University (CICS-NC)

Remote Sensing and Applications Division/NCDC

151 Patton Ave, suite 410

Asheville, NC 28801-5001

Ge.Peng@xxxxxxxx

Office: (828)257-3009

Fax: (828)271-4328

 

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On Thu, Feb 14, 2013 at 7:24 PM, Ryo Furue <furue@xxxxxxxxxx> wrote:

Hi Bill,

> I've done some more checks on this. I have simplified my scripts down to a
> very simple multi-panel shade plot and the problem persists and appears to
> be the same issue reported back in 2008
> (http://www.pmel.noaa.gov/maillists/tmap/ferret_users/fu_2008/msg00470.html
> ) and again in 2009
> (http://www.pmel.noaa.gov/maillists/tmap/ferret_users/fu_2009/msg00451.html
> ). This is a pretty dangerous bug because the error is not always obvious
> and it would be easy to not catch a one level error if many levels were
> selected. In the 2008 thread the problem was blamed on some axis
> manipulation. However, in my case I can reproduce the problem with just a
> series of basic shade commands (see script below).

You may be interested in the workaround I proposed in 2009:

http://www.pmel.noaa.gov/maillists/tmap/ferret_users/fu_2009/msg00216.html

I've been able to reproduce your problem with your original script,
and I've modified it to the attached one, which solves the problem.

Cheers,
Ryo
--------------
!       use "../test.nc"

use "etopo120.cdf"

set v ul
shade/lev=5 rose

ppl shaset reset  !! <--

set v ur
shade/lev=5 rose

ppl shaset reset  !! <--

set v ll
shade/lev=5 rose

ppl shaset reset  !! <--

set v lr
shade/lev=5 rose
shade/ov/nolab/lev=5 rose

frame/file="test.gif"