Hi, Did you have a look at the package adehabitatLT?
https://cran.r-project.org/web/packages/adehabitatLT/vignettes/adehabitatLT.pdf It deals with trajectories based on points ordered by date. Jerome 2017-01-13 11:41 GMT+01:00 marta azores <martazo...@gmail.com>: > Thanks for your quick reply to my question, > > This ten points are ordered by time (date + time), and I know ,the points > are all connected. I didn't include the column with the time in this > example, to make it simple. > > After read your messages, I was looking the minimum spanning tree for the > vertices. > The advantage with the function "shortestPath" is that you have as result a > spatial line output, which I need it. > However, the minimum spanning tree give as output an ordiplot. > > Is it possible to transform the ordiplot into spatialLines? > > Thanks for your answers > > Marta > > > > 2017-01-12 20:03 GMT-01:00 Eric Carr <c...@nimbios.org>: > > > Generically independent of R, A graph and the connectivity between points > > needs defined before a shortest path algorithm can be applied. If it > > assumes all points are connected, than the shortest path will be a > straight > > line. What you are looking for is some sort of minimum spanning tree > for > > the vertices. > > Eric > > > > On Thu, Jan 12, 2017 at 11:17 AM, marta azores <martazo...@gmail.com> > > wrote: > > > >> Dear forum members, > >> > >> I would like to know how join several points with the aim to track a > ship. > >> > >> After reading the documentation of some packages, I decided to use the > >> function shortestPath, but I only got the line between the first and the > >> last location of my points list. I need the complete survey, including > also > >> the middle points. I try a loop to build the survey of the boats using > >> their locations, but It didn't work to me. > >> > >> > >> Any idea? > >> > >> Thanks in advance, > >> > >> Marta > >> > >> #script# it's also attached in a R.file: question loop2.R > >> ########################################################## > >> # > >> #raster# it's attached > >> azoTS1<- raster("C:/Users/Documents/azoTS1.tif")#wgs84 > >> # > >> #10 points# it's attached > >> boat <- read.table("C:/Users/Documents/10pontos.csv", header=TRUE, > >> sep=",", na.strings="NA", dec=".", strip.white=TRUE)# > >> head(boat) > >> > >> #raster to transitionlayer > >> trCostS4<- transition(1/azoTS1, mean, directions=4) > >> > >> # points to spatialpointsdataframe > >> x=boat$Long1 > >> y=boat$Lat1 > >> coords = cbind(x, y) > >> plot(coords) > >> sp = SpatialPoints(coords, proj4string=CRS("+proj=longlat +ellps=WGS84 > >> +datum=WGS84"), bbox = NULL) > >> sp > >> spdf=SpatialPointsDataFrame(sp,boat) > >> spdf > >> nrow(spdf) > >> plot(sp,axes=TRUE) > >> plot(spdf,add=TRUE, axes=TRUE) > >> > >> #shortestpath > >> > >> ## 1) this script only join the first point of the list and the last > one, > >> and the points in the middle are not used. > >> CostpathSPdf <- shortestPath(trCostS4, spdf[1,], spdf[10,], > >> output="SpatialLines") > >> plot(CostpathSPdf,add=TRUE,axes=TRUE,col=2)#R_plot1.png (it's attached) > >> > >> ## 2) this script didn't work to me > >> > >> #first way from website: http://stackoverflow.com/quest > >> ions/8127066/loop-or-sapply-function-for-multiple-least- > >> cost-analysis-in-r?answertab=active#tab-top > >> for(i in 1:nrow(spdf)) { > >> # Computation > >> Costpath <- shortestPath(trCostS4, spdf[i,], spdf[10,], > >> output="SpatialLines") > >> plot(Costpath) > >> > >> } > >> > >> #Error in validObject(.Object) : > >> #invalid class “SpatialLines” object: bbox should never contain infinite > >> values > >> > >> _______________________________________________ > >> R-sig-Geo mailing list > >> R-sig-Geo@r-project.org > >> https://stat.ethz.ch/mailman/listinfo/r-sig-geo > >> > > > > > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > -- Jérôme Mathieu <http://www.jerome-mathieu.com/> Université Pierre & Marie Curie <http://www.upmc.fr/> Institute of Ecology and Environmental Science (Paris) <https://ieesparis.ufr918.upmc.fr/> Team EERI 4 place Jussieu Tour 44-45, 5th floor, door 514 75005 Paris tel: 01 44 27 34 22 [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo