[R-sig-Geo] How to crop a shapefile ?

[Renaud Lancelot]

Hi Baptiste,

I recently met a similar issue, and ended to the solution described here 
(unfortunately, it's in French :-)): 
ftp://ftp.cirad.fr/pub/group-r/groupe-r/Fiches/Foret.pdf

It uses point.in.polygon (package sp), and it is adapted to the special 
case of the shapefile containing polygons. Perhaps you can adapt it for 
polylines, possibly reversing the test (points of the lines falling into 
the area of interest for you).

I would be interested to hear about any alternative / better solution.

All the best,

Renaud

Baptiste Coulmont a écrit :
> Hi,
> 
> I'm working with R and various shapefiles created by the OpenStreetMap
> project. Those shapefiles (the roads in particular) are quite big.
> 
> How can I crop (or "trim", or "prune" those objects -- once in a
> SpatialLineDataFrame -- if I need to work not on a national level but
> on a municipal level ?
> 
> Is it possible to create a subset of a smaller zone ?
> Coordinates:
>          min       max
> r1  2.560776  6.403847
> r2 49.493613 51.505419
> 
> Thansk,
> B. Coulmont
> 

-- 
Renaud Lancelot
EDEN Project, coordinator
http://www.eden-fp6project.net/
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