Pacific Centric Low resolution World Map
This is an alternative version of the world database
based on latitudes [0, 360), which then has the Pacific
Ocean in the centre of the map.
data(world2MapEnv)
The data file is merely a character string which
specifies the name of an environment variable which contains the
base location of the binary files used by the map drawing functions.
This environment variable (R_MAP_DATA_DIR_WORLD for the datasets in the
maps package) is set at package load time if it does not
already exist. Hence setting the environment variable before loading
the package can override the default location of the binary datasets.
This data set is in fact largely obsolete. Often the same (more general) result can be obtained by using wrapping:
map("world", wrap=c(0,360))
This will also work fine with fill=TRUE or any other appropriate longitude interval (e.g. c(-90,270)).
However, world2 is useful when setting xlim to an interval crossing the 180 meridian.
The Natural Earth data set is available from http://www.naturalearthdata.com.
Richard A. Becker, and Allan R. Wilks, "Maps in S", AT\&T Bell Laboratories Statistics Research Report [93.2], 1993.
Richard A. Becker, and Allan R. Wilks, "Constructing a Geographical Database", AT\&T Bell Laboratories Statistics Research Report [95.2], 1995.
map('world2', xlim = c(100, 300))
map.axes()
# xlim is performed before wrapping:
map('world', wrap=c(0,360), xlim = c(100, 300))
# so to emulate "world2":
ww2 <- map('world', wrap=c(0,360), plot=FALSE, fill=TRUE)
map(ww2, xlim = c(100, 300), fill=TRUE)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.