north.arrow: Add a north arrow to a map

In GISTools: Some further GIS capabilities for R

Description

Draws a north arrow on a map.

Usage

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

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.

Details

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

Value

None.

Author(s)

Chris Brunsdon

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)')

Example output

Loading required package: maptools
Loading required package: sp
Checking rgeos availability: TRUE
Loading required package: RColorBrewer
Loading required package: MASS
Loading required package: rgeos
rgeos version: 0.3-23, (SVN revision 546)
 GEOS runtime version: 3.4.2-CAPI-1.8.2 r3921 
 Linking to sp version: 1.2-3 
 Polygon checking: TRUE 

GISTools documentation built on May 6, 2019, 1:09 a.m.