R: Plot of the world

world {fields}

R Documentation

Plot of the world

Description

Plots quickly, medium resolution outlines of large land masses and bodies of water.

Usage

world(ylim = c(-90, 90), xlim = NULL, add = FALSE, asp = 1,
                 xlab = "", ylab = "", xaxt = "n", yaxt = "n", eps =
                 0.1, col=1,shift = FALSE, 
                 fill=FALSE, col.water="white", col.land="darkgrey", ...)

world.color(xlim= c(-180,180), ylim=c(-90,90), 
             col.water="white",col.land="darkgrey", ... )

Arguments

`ylim`	range of latitudes
`xlim`	range of longitudes
`add`	logical; if true will add the world map to current plot.
`asp`	aspect ratio used if `add` is false, see `plot.default`.
`xlab,ylab`	labels for x- and y-axis; empty by default.
`xaxt,yaxt`	axis type for x- and y-axis; empty by default.
`eps`	Tolerance to decide when to insert line break about 0 if map is to be shifted. (leave this at .1)
`shift`	If TRUE shifts to be centered on the Dateline and longitude runs from 0 to 360. If FALSE centers on Prime Meridian and longitude runs from -180 to 180.
`col`	Color for map lines when fill is FALSE.
`fill`	If FALSE draws land outlines. If TRUE fills in land and water with different colors.
`col.land`	Color for land filling.
`col.water`	Color for water filling.
`...`	If the land is not filled these are graphical arguments that are passed to the `lines` (and `plot` if `add` is false) function that draws the outline.

If fill is TRUE then these arguments are passed to the polygon function that does the filling.

Details

Both functions use the FIELDS dataset world.dat for the coordinates. The main advantage of this function is that it is fast and easy to modify. The shift option to center over the dateline is useful because often plots of oceanic and atmospheric information center the map this way.

The function world.color can be used separately but is also called by world with fill being TRUE. When used alone it will just add the colored landmasses and water to an existing plot. It is easy to modify just to add the land masses and use the existing back ground color as water. Unfortunately world.color will not work when shift is TRUE. The current code could be modified if you need this option. Thanks to Steve McIntyre for suggesting and testin the fill option.

Examples


world()
# add the US
US( add=TRUE,col="blue")

world( fill=TRUE) # land filled in dark grey 

## Western Europe (*which* big islands are missing?)
## with a coordinate grid:

world(xlim=c(-10,18),ylim=c(36,60), 
    xaxt = "s", yaxt = "s", fill=TRUE, col.land="darkgreen")

box() # add back in the box that was obscured by the ocean fill.

# add back in outline of land.
world( add=TRUE,lwd=1.5, col="green")

grid()