berryFunctions (version 1.7.1)

circle: draw circle with a given radius

Description

draws a filled circle with a certain radius using polygon and sin

Usage

circle(x, y, r, locnum=100, ...)

Arguments

x

x coordinate

y

y coordinate

r

radius in units of current plot

locnum

number of calculated points on the circle. DEFAULT: 100

...

further arguments passed to polygon, like col, border, lwd

Value

• none. Used for drawing.

See Also

polygon

Examples

plot(1:20, type="n", asp=1)
circle(5,5, r=3)   # 1:1 aspect shows they're really circles and not ellipses.
circle(15,10, r=4, locnum=12, col=2, border=4, lwd=3)

# can not be vectorized:
x <- sample(1:20, 15) ;  y <- sample(1:20, 15) ; r <- runif(20)*3
circle(x,y,r, col=rgb(1,0.5,0,alpha=0.4), border=NA)
for(i in 1:15) circle(x[i],y[i],r[i], col=rgb(1,0.5,0,alpha=0.4), border=NA)