Draw an Ellipse
Draw one or several ellipses on an existing plot.
DrawEllipse(x = 0, y = x, radius.x = 1, radius.y = 0.5, rot = 0,
nv = 100, border = par("fg"), col = par("bg"),
lty = par("lty"), lwd = par("lwd"), plot = TRUE)x, y |
the x and y co-ordinates for the centre(s) of the ellipse(s). |
radius.x |
a scalar or a vector giving the semi-major axis of the ellipse. |
radius.y |
a scalar or a vector giving the semi-minor axis of the ellipse. |
rot |
angle of rotation in radians. |
nv |
number of vertices to draw the ellipses. |
border |
color for borders. The default is |
col |
color(s) to fill or shade the annulus sector with. The default |
lty |
line type for borders and shading; defaults to |
lwd |
line width for borders and shading. |
plot |
logical. If |
Use DegToRad if you want to define rotation angle in degrees.
The function invisibly returns a list of the calculated coordinates for all shapes.
Andri Signorell <andri@signorell.net>
par(mfrow=c(1,2))
Canvas()
DrawEllipse(rot = c(1:3) * pi/3, col=SetAlpha(c("blue","red","green"), 0.5) )
plot(cars)
m <- var(cars)
eig <- eigen(m)
eig.val <- sqrt(eig$values)
eig.vec <- eig$vectors
DrawEllipse(x=mean(cars$speed), y=mean(cars$dist), radius.x=eig.val[1] , radius.y=eig.val[2]
, rot=acos(eig.vec[1,1]), border="blue", lwd=3)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.