GISTools (version 1.0-1)

North Arrow: Add a north arrow to a map

Description

Draws a north arrow on a map.

Usage

north.arrow(xb,yb,len,lab='NORTH',cex.lab=1,tcol='black',...)

Value

None.

Arguments

xb

The x-centre (in map units) of the arrow base.

yb

The y-centre (in map units) of the arrow base.

len

The length (in map units) of the arrow base.

lab

The label for the arrow.

cex.lab

Scale factor for the label for the arrow.

tcol

The colour of the label text.

...

Other graphical parameters passed to the drawing of the arrow.

Author

Chris Brunsdon

Details

Draws a north arrow on a map. The arrow itself is drawn using polygon and any extra parameters are passed to this call.

See Also

map.scale

Examples

# Read in map data for New Haven
data(newhaven)
# Plot census block boundaries
plot(blocks)
# Add a north arrow
north.arrow(534750,152000,miles2ft(0.5),col='cyan')
# ... and a title
title('New Haven (CT)')