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Last data update: 2014.03.03

R: Add a north arrow to a map

North Arrow

R Documentation

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',...)

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

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)')

Results


R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

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Type 'demo()' for some demos, 'help()' for on-line help, or
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> library(GISTools)
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: 0.3-19, (SVN revision 524)
 GEOS runtime version: 3.5.0-CAPI-1.9.0 r4084 
 Linking to sp version: 1.2-3 
 Polygon checking: TRUE 

> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/GISTools/north.arrow.Rd_%03d_medium.png", width=480, height=480)
> ### Name: North Arrow
> ### Title: Add a north arrow to a map
> ### Aliases: north.arrow
> 
> ### ** 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)')
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>