NSarrow {GEOmap}

North-South Weather Vane Arrow

Description

Add north-south weather vane arrow figure

Usage

NSarrow(x = NULL, y = NULL, R = 1, col.arrow = 1, col.N = 1,
col.circ = 1, rot = 0, PMAT = NULL)

Arguments

x

X-location vector, if list, include both x and y values

y

Y-location vector, not needed if x is a list

R

radius, in plot coordinates

col.arrow

color for arrow, default="black"

col.N

color for N symbol

col.circ

color for circle

rot

rotation angle, degrees

PMAT

projection matrix, output of persp

Details

The location list should have 2 values for x and y each, the second value for y determines the radius R if it is not provided. The first element of y is the center of the weather vane. If no x-list is provided, the interactive locator function is invoked and a list is returned for future work.

Value

x

x-location

y

y-location

Author(s)

Jonathan M. Lees<[e-mail]>

See Also

zebra

Examples

plot(c(1:10), c(1:10), type='n')

x=c(2,2)
y = c(8,9)

NSarrow(list(x=x, y=y))

##### move over and repeat, with rotation of 25 degrees west

x=c(5,5)
y = c(8,9)

NSarrow(list(x=x, y=y), rot=25)