Dear Jonas,

I already had to deal with such an issue.
Your can use the joinPolys function from the package PBSmapping, with "INT"
as operation.

The maptools package has functions SpatialPolygons2PolySet and
PolySet2SpatialPolygons to switch between formats suitable for sp or
PBSmapping.

Hope this helps.
Yves


On 26 October 2010 10:18, jonas garcia <garcia.jonas80@googlemail.com>wrote:

> Thanks for your reply,
>
> My main issue is that I don't have any equations to generate the data, just
> a bunch of points, each corresponding to a polygon.
>
> I was looking in package "sp" and there is a function to calculate areas (
> areapl()), but not for intersecting polygons. Is there any other package
> that does this?
> Thanks
> On Tue, Oct 26, 2010 at 3:38 AM, Remko Duursma <remkoduursma@gmail.com
> >wrote:
>
> >
> > Dear Jonas,
> >
> > if you can write the difference in y-values between your polygons as a
> > function, you can use
> > integrate() to get the area between the polygons.
> >
> > It sounds like perhaps your x-values will not match between the polygons
> > because they come from different sources, so you probably have to do some
> > interpolating (with ?approx).
> >
> >
> > hope that helps,
> > Remko
> > --
> > View this message in context:
> >
> http://r.789695.n4.nabble.com/calculate-area-between-intersecting-polygons-tp3012980p3013059.html
> > Sent from the R help mailing list archive at Nabble.com.
> >
> > ______________________________________________
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> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html<
> http://www.r-project.org/posting-guide.html>
> > and provide commented, minimal, self-contained, reproducible code.
> >
>
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> ______________________________________________
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