Calculate geographic/euclidian distance between consecutive XY-pairs
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.Brownrigg at 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
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