[R-sig-Geo] convert point data to count data

[Mathieu Basille]

Hi Karla,

Appart from spatstat/sp, you might give a try to adehabitat: there's a 
function called 'ascgen' which does exactly what you want: create a grid 
of a given resolution according to the points you have, with the number 
of points in each cell. Check ?ascgen (and especially the example) for 
further details. There are eventually functions to convert maps from 
adehabitat to sp if needed.

Hope this helps,
Mathieu.


Karla Falk a écrit :
> Hi,
> 
>   I have a data set of points that I would like to convert to grid cell counts.  Ultimately I would like to end up with a table that has an x-y coordinate for each grid cell, and the count of the # of points falling in each grid cell.  Does anyone know a way to do this in R?  I have been playing around with using quadratcounts in spatstat, and the overlay methods in sp, but with both I can't figure out how to get an output table of the cell counts (including counts of zero's) with the corresponding x-y utm of the grid cell.  Any help would be greatly appreciated!
> 
> Thanks,
> Karla


-- 

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 > Mathieu Basille, PhD

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 > Laboratoire de Biométrie et Biologie Évolutive
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