Title: Swiss Roll Source: Borg and Groenen (2005) Description: Data generated on the surface of a Swiss roll. The points lie on the surface of a 2D plane that is rolled. The coordinates are for row i are given by: x_i = .5*sin(4*pi*v_i) y_i = u_i-.5 z_i = .5*v_i*cos(4*pi*v_i) for uniformly distributed v_i and u_i between zero and one.