Hi Ray, thank you very much. That one-line approach is what I was looking for. A very simple but very efficient way without loading any other packages.
/j On Tue, Dec 18, 2012 at 11:17 AM, Ray Brownrigg <ray.brownr...@ecs.vuw.ac.nz> wrote: > On 18/12/2012 10:56 p.m., Johannes Radinger wrote: >> >> Hi, >> >> I have a dataframe containing 3 columns: >> >> data.frame(X=c(100,102,104,102,103),Y=c(12,14,14,13,16),Time=c(1,2,3,4,5)) >> >> where X and Y are coordinates and "Time" refers to an index of a timestep. >> Now I would like to get the distance between the consecutive timesteps. >> >> This should actually provide a vector of length=4, representing the >> euclidian >> resp. geopgraphic distance between the first and the second, and the >> second >> and the third timestep and so on... >> >> Is there a simple way to calculate this and get the resulting vector >> as a result? >> Or can anyone give an example? > > How about something like: > coords <- > data.frame(X=c(100,102,104,102,103),Y=c(12,14,14,13,16),Time=c(1,2,3,4,5)) > with(coords, sqrt(diff(X)^2 + diff(Y)^2)) > > Ray Brownrigg >> >> >> best regards, >> /j >> >> ______________________________________________ >> 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. > > > ______________________________________________ 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.
