Drawing a circle - take 2

Exercise Type: Implementation

Instructions

Write a function to repeat the plotting above based on the following parameters (similar to this earlier exercise: Drawing a circle).

name	Circle()
arguments	x : x coordinate of origin
	y : y coordinate of origin
	r : radius
	by : the angle step size in degrees
	plot : logical, if TRUE, then the circle should be plotted
return	A 2D matrix with x and y coordinates

Try to implement this exercise using vectorization principles only, without using either for or while loops!

Important: do not draw the basic plot with the function, assume that people will call to it, before calling to Circle(). The plot above should be redrawable with these instructions:

plot(0,0)
circle <- Circle(x=0, y=0, r=1, by=5, plot=TRUE)