Dear All,
Please have a look at the snippet here
http://bit.ly/2mVS8me
This short code addresses precisely one of my needs: to superimpose a
network (created with the igraph library) to a geographical map.
Unlike the case of the example, where a single country is enough, I
need to have a world map in R to which superimpose the network.
Seen that I am far from an expert about plotting maps in R (you may
want to resort to a purely ggplot oriented solution for the map, but
then you need to translate your network into something ggplot
understands -- see http://bit.ly/2mVSOIk ).
For me it would be way simpler to follow the footsteps of the work
done in the previous link, but I cannot download from GADM a world
map.
Does anybody know how to achieve that?
Regards
Lorenzo
#######################################################?
library(raster)
library(igraph)
greece <- getData('GADM', country='GRC', level=1)
df<-data.frame("from" = c("Athens", "Iraklio",
"Thessaloniki",
"Patra"), "to"= c("Thessaloniki",
"Thessaloniki", "Athens",
"Iraklio"))
meta <- data.frame("name"=c("Athens",
"Iraklio", "Thessaloniki",
"Patra"),
"lon"=c(23.72800,25.13356,22.94090,21.73507),
"lat"=c(37.98415,35.33349,40.63229,38.24628))
g <- graph.data.frame(df, directed=T,
vertices=meta)
lo <- as.matrix(meta[,2:3])
plot(greece)
plot(g, layout=lo, add = TRUE, rescale = FALSE)
Hi Lorenzo, See: http://www.gadm.org/version2 Jim On Wed, Mar 15, 2017 at 1:57 AM, Lorenzo Isella <lorenzo.isella at gmail.com> wrote:> Dear All, > Please have a look at the snippet here > > http://bit.ly/2mVS8me > > This short code addresses precisely one of my needs: to superimpose a > network (created with the igraph library) to a geographical map. > Unlike the case of the example, where a single country is enough, I > need to have a world map in R to which superimpose the network. > Seen that I am far from an expert about plotting maps in R (you may > want to resort to a purely ggplot oriented solution for the map, but > then you need to translate your network into something ggplot > understands -- see http://bit.ly/2mVSOIk ). > For me it would be way simpler to follow the footsteps of the work > done in the previous link, but I cannot download from GADM a world > map. > Does anybody know how to achieve that? > Regards > > Lorenzo > > > #######################################################? > library(raster) > library(igraph) > greece <- getData('GADM', country='GRC', level=1) > df<-data.frame("from" = c("Athens", "Iraklio", "Thessaloniki", > "Patra"), "to"= c("Thessaloniki", "Thessaloniki", "Athens", > "Iraklio")) > meta <- data.frame("name"=c("Athens", "Iraklio", "Thessaloniki", > "Patra"), > "lon"=c(23.72800,25.13356,22.94090,21.73507), > "lat"=c(37.98415,35.33349,40.63229,38.24628)) > g <- graph.data.frame(df, directed=T, > vertices=meta) > lo <- as.matrix(meta[,2:3]) > plot(greece) > plot(g, layout=lo, add = TRUE, rescale > FALSE) > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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.
Thanks, I had also seen that, but I was hoping to avoid dealing with the shapefiles and to download the world map as a spatial polygon data frame. Cheers Lorenzo On Wed, Mar 15, 2017 at 09:21:54AM +1100, Jim Lemon wrote:>Hi Lorenzo, >See: > >http://www.gadm.org/version2 > >Jim > > >On Wed, Mar 15, 2017 at 1:57 AM, Lorenzo Isella ><lorenzo.isella at gmail.com> wrote: >> Dear All, >> Please have a look at the snippet here >> >> http://bit.ly/2mVS8me >> >> This short code addresses precisely one of my needs: to superimpose a >> network (created with the igraph library) to a geographical map. >> Unlike the case of the example, where a single country is enough, I >> need to have a world map in R to which superimpose the network. >> Seen that I am far from an expert about plotting maps in R (you may >> want to resort to a purely ggplot oriented solution for the map, but >> then you need to translate your network into something ggplot >> understands -- see http://bit.ly/2mVSOIk ). >> For me it would be way simpler to follow the footsteps of the work >> done in the previous link, but I cannot download from GADM a world >> map. >> Does anybody know how to achieve that? >> Regards >> >> Lorenzo >> >> >> #######################################################? >> library(raster) >> library(igraph) >> greece <- getData('GADM', country='GRC', level=1) >> df<-data.frame("from" = c("Athens", "Iraklio", "Thessaloniki", >> "Patra"), "to"= c("Thessaloniki", "Thessaloniki", "Athens", >> "Iraklio")) >> meta <- data.frame("name"=c("Athens", "Iraklio", "Thessaloniki", >> "Patra"), >> "lon"=c(23.72800,25.13356,22.94090,21.73507), >> "lat"=c(37.98415,35.33349,40.63229,38.24628)) >> g <- graph.data.frame(df, directed=T, >> vertices=meta) >> lo <- as.matrix(meta[,2:3]) >> plot(greece) >> plot(g, layout=lo, add = TRUE, rescale >> FALSE) >> >> ______________________________________________ >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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.