From: Daniel Moore on 28 May 2010 19:29
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## Geometric Intersections (#233)
This week's quiz is to detect the intersections of various geometric
elements: circles, lines, and polygons.
A circle is defined by a point and a radius.
point = [6, 3]
radius = 5
a = Circle.new(point, radius)
A line can be defined by two points, or a point and a slope.
p1 = [0, 0]
p2 = [4, 2]
line = Line.new(p1, p2)
slope = 0.5
line = Line.new(p1, slope)
A polygon can be defined as a collection of points.
b1 = [2, 9]
b2 = [1, 3]
b3 = [7, 5]
b = Polygon.new(b1, b2, b3)
def intersect(a, b)
# Should return true or false indicating whether or not
# a and b intersect. a and b can be any circle, line or
You may also find it more natural to define a.intersect(b) or
b.intersect(a). The relation should be symmetric and reflexive, though
Which methods you choose to add to the geometric elements is up to
you, the only hard requirement is that the intersect method(s) return
the correct truth values.
Extra Credit: handle the "edge" cases of the polygon comprised of one
point (a single point) or two points (a line segment).
Extra Extra Credit: Provide a graphical and colorful output indicating