[R] Can I create an European map using the map function in R

[Ray Brownrigg]

On Tue, 27 Jul 2010, Maomao Luo wrote:
> Hi,
>
> I am trying to create a spatial weight matrix based on the neighboring
> relationship among Europan countries.  Can I use the map function in R to
> generate a European map and then use this map to build the w weight matrix?
>  So far, I cannot create a map for Finland using the map function.
>
It is not clear to me what you mean by "... use this map to build the w weight matrix".  
How can you use an image on the screen to generate a matrix?

However, to get the map of Europe using the maps package, try something like this:

library(maps)
m <- map("world", xlim=c(-10, 30), ylim=c(35, 60))
Europe <- sort(m$names)
fix(Europe)	# remove anything you don't need
map("world", Europe, exact=T)

Note for example, you will need to leave in "UK:Great Britain" and "UK:Northern Ireland", 
since there is no country called "UK".  Similarly, Malta is named as "Malta:Malta".

Hope this helps,
Ray Brownrigg
>
> Also, I am not very sure about the steps in importing external map data and
> use that information to generate a spatial weight matrix in R.  Could
> anyone show me how to implement this using European countries as an
> example?
>
Pass.

> Thanks a lot for your help.
>
> Maomao