Tips and questions re mapping...

First key point is that simplifying the map is a really good idea.

package: rmapshaper
function: ms_simplify
Code: gadmNabS <- ms_simplify(gadmNab, keep = 0.01)

N.B. Plots much faster and looks OK.
Need to play and optimise this.


Issues re "gpclib" to bind names into the object with tidy()
http://stackoverflow.com/questions/21093399/how-to-turn-gpclibpermit-to-true





Some other links about this:

http://stackoverflow.com/questions/12629647/adding-geom-path-and-geom-text-to-the-same-ggplot-generates-error-in-r

https://gis.stackexchange.com/questions/43543/how-to-calculate-polygon-centroids-in-r-for-non-contiguous-shapes

http://ggplot2.tidyverse.org/reference/coord_map.html

http://ggplot2.tidyverse.org/reference/scale_gradient.html

http://stackoverflow.com/questions/6181653/creating-a-more-continuous-color-palette-in-r-ggplot2-lattice-or-latticeextra

http://ggplot2.tidyverse.org/reference/scale_brewer.html

http://stackoverflow.com/questions/21093399/how-to-turn-gpclibpermit-to-true