Hi Simon A combination of functions gDistance, gBuffer and gIntersects from package rgeos should do the job. Also, have a look at www.naturalearthdata.com. They have various shapefiles with coastlines and land polygons, though I don't know how the resolution compares with the worldHires database. Cheers, Francois Rousseu
> Date: Thu, 14 Jul 2011 05:43:23 -0700 > From: s.j.good...@leeds.ac.uk > To: r-help@r-project.org > Subject: [R] calculating distance inland from coastline > > Hi All, > > Does anybody know of any existing functions that will calculate distance > inland from a coastline? > > It's possible to test if a lon,lat location is land or sea using > map.where(), but I need to add a buffer to this of say 2km, to allow for > points that are just on the coast, and below the resolution of the > worldHires database. > > I'm working with a marine mammal satellite telemetry dataset and wish to > filter out spurious locations on land. > > On another issue, does anybody know of any free vector map datasets that are > more up to date and have a higher resolution than the worldHires database > from the 'maps' package. > > Thanks, Simon > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/calculating-distance-inland-from-coastline-tp3667464p3667464.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
