[R-sig-Geo] map projection problem

[Melanie Abecassis]

Hi,
I am unsuccessfully trying to change the map projection  in map function 
of the maps library.

Here is my code :

library(maps)
library(mapdata)
library(mapproj)

map(database = "world", fill = TRUE, col = 1, plot = TRUE,add=F, 
xlim = c(-200,-120), ylim = c(-5,45))
map.axes()

This gives me a map centered on Hawaii.


I now want to have *the same map but in the mercator projection* :

map(database = "world", fill = TRUE, col = 1, plot = TRUE,add=F, 
projection="mercator", xlim = c(-200,-120), ylim = c(-5,45))
map.axes()

And I get a weird map of the US  and parts of Canada only.


Then I tried this :

A=mapproject(c(-200,-120), c(-5,45), projection="mercator")

map(database = "world", fill = TRUE, col = 1, plot = TRUE,add=F, 
projection="mercator", xlim = A$x, ylim = A$y)
map.axes()

which should be the correct way to do this I think, but I get this :
Error in map.poly(database, regions, exact, xlim, ylim, boundary, 
interior,  :
  nothing to draw: all regions out of bounds

Could anyone help me with this ?
Thanks a lot,
Melanie