I am not calling CGAL from R yet - currently I am just using dumping x y
points from R to alpha shapes in a loosely coupled fashion and then
reading the results back into R and into a postGIS database. The alpha
shapes is a "concave" hull routine. I need to call the cgal C++ code
from R and will soon work on that. I understand it should be possible.
It would be great to have CGAL bindings in R.
Murray
G. Allegri wrote:
> Great, I didn't know it... I just made a rapid try some time ago but
> it failed because I didn't use the ""
>
> I'm sorry for bothering, how are you using R with CGAL?
>
>
> 2008/3/31, Murray Richardson <[EMAIL PROTECTED]>:
>
>> See below. Haven't tried this yet.
>>
>> Yes that is what CGAL stands for.
>>
>> Murray
>>
>>
>>
>>
>>
>>
>> Hi Murray,
>>
>> Regarding the first question, you can read into R first and then output
>> it again. You could also call ogr2ogr using a system call like:
>>
>> system("ogr2ogr normal syntax stuff")
>>
>> cheers,
>> Paul
>>
>>
>>
>> G. Allegri wrote:
>> > Hi Murray.
>> > About the first question. As far as I understand, you're working in R
>> > on a *imported* PostGIS layer (I suppose you use rgdal to do it,
>> > right?). Then you would need to export it to a shapefile (easily done
>> > with writeOGR). Why are you considering the use of ogr2ogr? As you
>> > probably know, it's a binary callable from a command line, and it's
>> > not possible (AFAIK) to do it from R...
>> >
>> > I dont' understand your second question...
>> >
>> >> Or even better could ogr be used to do this directly on a postGIS layer?
>> >>
>> > What do you mean?
>> >
>> > Giovanni
>> >
>> >
>>
>>
>
>
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