adds part of a colored circle to a plot

adds (part of) a colored circle to a plot; an arrow can be drawn at a specified position

plotcircle(r = 1, ...)

Arguments

r

radius of circle.

...

arguments passed to function plotellipse.

Author

Karline Soetaert <karline.soetaert@nioz.nl>

Details

plotcircle calls plotellipse, making sure that the figure drawn effectively looks like a circle. For graphs that have both axes of equal size, the circle will be equal to the ellipse with equal rx and ry. See second example

see plotellipse for details

See also

plotellipse to draw ellipses

Examples

# symmetrical axes
emptyplot(c(0, 1))
plotcircle(mid = c(0.5, 0.5), r = 0.25, from = 0, to = 3*pi/2,
           arrow = TRUE, arr.pos = 0.5, col = "red")
# symmetrical
plotellipse(mid = c(0.5, 0.5), rx = 0.2, ry = 0.2, 
           arrow = TRUE, arr.pos = 0.5, col = "blue")



#non-symmetrical axes
emptyplot(c(0, 1), c(0, 2), main = "plotcircle", asp = FALSE)
plotcircle(mid = c(0.5, 0.5), r = 0.25, from = 0, to = 3*pi/2,
           arrow = TRUE, arr.pos = 0.5, col = "red")
plotellipse(mid = c(0.5, 0.5), rx = 0.25, ry = 0.25, 
           arrow = TRUE, arr.pos = 0.5, col = "blue")