[gradsusr] how to create quantile scale

[Huddleston, John]

Ondrej

open your CTL
set gxout shaded
d variable
q shades

and parse the output with subset

John Huddleston

________________________________________
From: gradsusr-bounces at gradsusr.org [gradsusr-bounces at gradsusr.org] On Behalf Of Ondrej Vlcek [vlcek at chmi.cz]
Sent: Wednesday, September 14, 2011 1:24 AM
To: gradsusr at gradsusr.org
Subject: Re: [gradsusr] how to create quantile scale

Dear Bernd and John,
thank you for your quick answers and I am sorry, that I was not specific
enough.

I know how to set "clevs" and "ccol". But my problem is different. Example of
the image with which I am not satisfied is attached: most of the picture is
drown in purple (values <0.01). My problem is how to define "clevs" in such a
way that for each interval there would be approximately equal amount of pixels
in the map. Which basicly means to convert the 2D array into 1D, sort it in an
ascending order, determine values which correspond to the 10th, 20th, .. ,
90th quantile and use them to define "clevs".

Unfortunately I do not know GrADS functions which I could easily use for this
purpose.

I also note that I want to use this in an automatic GrADS script.

Ondrej