[R-sig-Geo] R: help to creating a points subset with R: Cut points shapefaile with a buffer polygon shapefile

[Paul Hiemstra]

Hi,

Please also send your replies to the mailing list, and not only to me 
personally. Other people might have better ideas than I have.

If your shapefile is too big for your memory, try to cut it up and do 
your analysis on a subset of both your point data and polygon data. And 
please provide us with information on you system, is it 64 bit or 32 
bit, how much memory, which version of R, which operating system. Look 
at the sessionInfo command to get some of this info. To get more hints 
as how to write good posts, please read the posting guide for the main R 
list, R-help.

cheers,
Paul

Alessandro schreef:
> Thanks for your help and Sorry for my ineptitude
>
> Do you tell about "Methods for spatially overlay-ing points (grids) and
> polygons layers" or "spatial overlay for points grids and polygons"? 
> I had see in help(sp) but, sorry, It's not very help clear for not expertise
> like me. I have this two shapefile (point and buffer) but the point is very
> hug dataset and read in maptools is not possible (memory crash down).
>
> Canopy (points)
> Buffer (polygon)
>
> I know that I must get a spatialPointsDataFrame (=canopy) then load the
> Polygon (=buffer), but after "I am in the middle of Ocean with a small ship"
>
> Thanks again if you could help me 
>
> Alessandro
>
>
>
>
> -----Messaggio originale-----
> Da: Paul Hiemstra [mailto:p.hiemstra at geo.uu.nl] 
> Inviato: mercoledì 25 febbraio 2009 23.24
> A: Alessandro
> Cc: r-sig-geo at stat.math.ethz.ch
> Oggetto: Re: [R-sig-Geo] help to creating a points subset with R: Cut points
> shapefaile with a buffer polygon shapefile
>
> Hi,
>
> Have you tried the overlay command in the sp package?
>
> cheers,
> Paul
>
> Alessandro schreef:
>   
>> Hi All Researcher, 
>>
>>  
>>
>> Thanks for help and suggestions. 
>>
>>  
>>
>> I have a points shapefile (soil) with one column [H] and a circular buffer
>> polygons (plots) with a column [ID identify. Ex: 1,2,3 etc etc]. I wish to
>> clip the points shapefile with the buffer and obtain a new points shape
>>     
> file
>   
>> (only the points inside the buffer) with two columns [ID of buffer and H).
>>
>>  
>>
>> I have with maptools problem with memory because every time my R
>>     
> crash-down.
>   
>>  
>>
>>  Any suggestions would be appreciated. 
>>
>>  
>>
>> Thanks again
>>
>>  
>>
>> Ale
>>
>>
>> 	[[alternative HTML version deleted]]
>>
>> _______________________________________________
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>> R-sig-Geo at stat.math.ethz.ch
>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>   
>>     
>
>
>   


-- 
Drs. Paul Hiemstra
Department of Physical Geography
Faculty of Geosciences
University of Utrecht
Heidelberglaan 2
P.O. Box 80.115
3508 TC Utrecht
Phone:  +3130 274 3113 Mon-Tue
Phone:  +3130 253 5773 Wed-Fri
http://intamap.geo.uu.nl/~paul