Description
This computational design algorithm is based on the parametric equation of a circle:
x = h + r cosθ y = k + r sinθ
Where h and k are the center point coordinates, r is the radius and θ is the angle between 0 and 360. In Dynamo, by defining the x and y at different angle positions and keeping the radius constant you get the points around the circle.
Of course interesting shapes can derive when you alter some parameters. For instance, making the radius variable produces a spiral-like form. Adding height to the points gives a 3D result. A heart shape can be obtained by playing with the radius values back and forth.
Ellipse
An ellipse is similar to the circle but you have to consider 2 radii instead of one:
x = h + r1 cosθ y = k + r2 sinθ