Hi Greg, thanks for your help. I found vectorFields, as suggested by Jim Lemon, in plotrix to be slightly easier (given my relatively basic R language knowledge!). Kind Regards, Conor
On 27 September 2013 22:07, Greg Snow <538...@gmail.com> wrote: > The ms.arrows along with my.symbols in the TeachingDemos package does not > require start and end points, it takes a single point along with the angle > and length (and the length can be a single constant to have all the arrows > the same length, or a variable to have different lengths). You can also > set an adjustment parameter to decide if the arrows should be centered on > the point, start at the point, or end at the point. > > The ms.arrows function was designed for exactly what you describe. > > > On Fri, Sep 27, 2013 at 12:56 PM, Conor Ryan <miol...@gmail.com> wrote: > >> I am trying to plot points on a map for each ship locations (lat/long), >> where >> each point is a line whose angle (degrees) denotes ships heading and whose >> line length denotes it's speed. Unfortunately arrows(); p.arrows (sfsmisc) >> and ms.arrows (TeachingDemos) require start and end coordinates but I only >> have a single coordinate and an angle to work with. Can you suggest any >> other packages or commands that might allow me to plot this? >> Alternatively, >> can anyone suggest a method of making 'angle' a vector quantity when using >> the arrows function? Any advice would be much appreciated! >> >> [[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. >> > > > > -- > Gregory (Greg) L. Snow Ph.D. > 538...@gmail.com > [[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.
