[gradsusr] Spatial trend using ltrend.gs

[Andrew Friedman]

Hi Jayakrishnan,

I don’t think what you’re doing is wrong, but you also can just display the second output, slope (s in your case).

USAGE: ltrend <input> [<output> [<slope> [<rmse>]]]
  <input>: input field. Can be any GrADS expression.
  <output>: output field, i.e., fitted trend line. Default=<input>.
  <slope>: slope of fitted trend line, i.e., change of <input> per time step.
  <rmse>: root mean square error.

-Andrew

> On Jun 11, 2018, at 5:56 AM, Jayakrishnan P.R <prjayakrishnan at gmail.com> wrote:
> 
> Dear Users,
>               I would like to calculate the spatial linear trend of temperature using long-term data and plot it using grads ltrend.gs. I would like to get a single plot which depicts the spatial trend at each grid point from t=1, t= last. I am doing like this. Kindly correct me if I am wrong.
> 
> open temp.nc
> 
> 'set t 1 last'
> 'ltrend mx2t mx2tl s e'
> 'set t 1'
> 'define a=mx2tl'
> 'set t last'
> 'define b=mx2tl'
> 'set gxout shaded'
> 'd b-a'
> 
> The obtained figure for the trend is attached herewith. Kindly help me to check I am right or wrong. 
> I am subtracting the last trend with the first trend to obtain a spatial map of the trend. 
> Thanks
> Jayakrishnan
> 
> 
> -- 
> Sincerely
> 
> **************************************************
> Dr. Jayakrishnan P.R
> Post Doctoral Research Fellow
> Science Technology Building
> School of System Science
> Beijing Normal University
> No. 96 XInjiekouwai Street
> Beijing 100875
> China
> Tel: +86-188 11005715
> 
> ****************************************************
> 
> 
> 
> 
> <trend.png>_______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr