[R] Count the number of unique days

[Jeff Newmiller]

Certainly it is possible. One way might involve using the "unique" function based on location and date before attaching the data to your SPDF.
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Sent from my phone. Please excuse my brevity.

On February 24, 2014 4:17:47 AM PST, bogdan_antonescu <bogdan.antonescu at manchester.ac.uk> wrote:
>Hi All, 
>
>I am working on a script to that is producing a lightning density map
>(numer
>of lightning flashes per area) based on a data set containing:
>date(year/month/day), time(hh/mm/ss), latitude, and longitude for each
>lightning flash. The attaches script is producing this map using a
>hexagonal
>grid. I am wondering if it is also possible to count the number of
>unique
>days in each grid cell, in order to produce a map with the number of
>day
>with lightning. 
>
>script:
>https://dl.dropboxusercontent.com/u/51871539/lightning_density.r
>data sample:
>https://dl.dropboxusercontent.com/u/51871539/lightning_test.csv
>
>Thank you very much for your help.
>
>Cheers,
>Bogdan
>
>
>
>
>--
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>
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