Add docstring

pytransform3d/geometry.py

@@ -4,12 +4,32 @@
 
 
 def unit_sphere_surface_grid(n_steps):
+ """Create grid on the surface of a unit sphere in 3D.
+
+ Parameters
+ ----------
+ n_steps : int
+ Number of discrete steps in each dimension of the surface.
+
+ Returns
+ -------
+ x : array, shape (n_steps, n_steps)
+ x-coordinates of grid points.
+
+ y : array, shape (n_steps, n_steps)
+ y-coordinates of grid points.
+
+ z : array, shape (n_steps, n_steps)
+ z-coordinates of grid points.
+ """
  phi, theta = np.mgrid[0.0:np.pi:n_steps * 1j,
  0.0:2.0 * np.pi:n_steps * 1j]
  sin_phi = np.sin(phi)
+
  x = sin_phi * np.cos(theta)
  y = sin_phi * np.sin(theta)
  z = np.cos(phi)
+
  return x, y, z