A Circle is a simple shape consisting of those points in a plane which are the same distance from a given point called the center. The common distance of the points of a circle from its center is called its radius. A diameter is a line segment whose endpoints lie on the circle and which passes through the centre of the circle. The length of a diameter is twice the length of the radius. A circle is never a polygon because it has no sides or vertices.
A Circle is a special ellipse in which the two foci are coincident. Circles are conic sections attained when a right circular cone is intersected with a plane perpendicular to the axis of the cone.
The parametric equations for the Circle are:
To plot function graph use the folowing script: