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Re: [ferret_users] Number of occurrence of data in a coarse grid



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> On 31 Aug 2011, at 11:44 PM, Russell Fiedler wrote:
> 
> ! How can I count the number of data points that fall in each gridbox?
> 
> ! put points into 1x1 bins on (0,2]x(0,2]
> 
> ! here are the points we want to bin
> 
> let xvals=zsequence({ 0.1, 2.0, 0.2 })
> let yvals=zsequence({ 0.1, 2.0, 0.2 })
> 
> ! Define our bounds Note promotion to 2D
> 
> let xl= i[i=1:2]-1+0*xvals
> let xh= i[i=1:2]+0*xvals
> let yl= j[j=1:2]-1+0*xvals
> let yh= j[j=1:2]+0*xvals
> 
> let isinboxx = if ( xvals le xh and xvals gt xl ) then 1 else 0
> let isinboxy = if ( yvals le yh and yvals gt yl ) then 1 else 0
> 
> let isinbothboxes = isinboxx*isinboxy
> let numinbox = isinbothboxes[z=@sum]
> 
> list numinbox
> 
>            VARIABLE : ISINBOTHBOXES[Z=@SUM]
>             SUBSET   : 2 by 2 points (X-Y)
>             Z        : 0.5 to 3.5
>             1      2
>             1      2
> 1   / 1:  2.000  0.000
> 2   / 2:  0.000  1.000


> On Jun 30, 2016, at 11:09 PM, Murali Kallungal <mkallungal@xxxxxxxxx> wrote:
> 
> Hi All
> I have 4 km sst data, due to cloud cover during monsoon months some data is missing.
> I assume a coarse grid (say 2°) and would like to know how many good data points in coarse grid w.r.t. data point in each day for my computation.
> Please help me to solve this problem
> 
> Thanks in advance
> Muraleedharan
> 
> -- 
> -------------------------------
> 
> Muraleedharan K.R
> -------------------------------
> Scientist 
> National Institute of Oceanography
> Regional Centre
> Salim Ali Road
> P.B. No. 1913
> Kochi - 682 018
> Kerala, India
> Ph (O): +91-484-2390306
> Fax:     +91-484-2390618
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> E-mail: muraleedharan@xxxxxxx



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