Re: [ferret_users] average values excluding zeroes

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi,
I think what you're doing looks correct.  What are you seeing?

One thing that may be going on is the region specification:

let temp=ci_data[x=65:95@ave,y=5:40@ave]

The context, x=65:95 and y=5:40, is being applied to the pt_in_poly 
expression and I think the x context is being applied to the arguments 
xci,yci

Try it with this instead - you have defined ci_data to be missing 
outside the region of interest, so it should give you the result you want.

  let temp=ci_data[x=@ave,y=@ave]

Another small suggestion, is to make sure your polygon is closed. Repeat 
the first value in the lists at the end.

See the region,

   yes? shade rf[d=1,l=18050]
   yes? plot/vs/line/over/nolab/thick xci, yci

Ansley

On 12/3/2014 7:13 AM, Nitin Patil wrote:
> Dear ferret users,
>
> I am averaging the area of interest and I am getting the mean, 
> standard deviation which counts zero also to get mean. How to exclude 
> the zero in the selected area grids and get the real mean value.
>
> Here is my script:
>
> let xci = 
> {77,79,79,83,83,84,84,83,83,82,82,80,80,79,79,76,76,73,73,72,72,74,74,75,75,77,77}
> let yci = 
> {27,27,25,25,24,24,21,20,20,19,18,18,17,17,16,16,15,15,15,18,21,21,23,23,24,24,24}
> let ci = pt_in_poly(rf[d=1],xci, yci)
> let ci_data = if ci eq 1 then ci*rf[d=1,l=18050:18171]
>
> let temp=ci_data[x=65:95@ave,y=5:40@ave]
> let sum=MISSING(temp,0)
> let sum_good=IFV temp then 1 else 0
> let count=sum_good
> let mean=sum/count
>
> stat mean
> sh sym stat*
> let varmean = ($stat_mean)
> let varstd = ($stat_std)
> list/norowlab/nohead/append/file=CI.txt varmean, varstd
>
> --------------------------
>
> --
> Regards,
> Nitin Patil