class_docstr: Create the arrays sphere_x, sphere_y, sphere_z to plot a sphere.
  
  Create the arrays sphere_x, sphere_y, sphere_z of values
  to plot the wireframe of a sphere.
  Their shape is (n_meridians, n_circles_latitude).
class_docstr_tok: ["Create","the","arrays","sphere_x",",","sphere_y",",","sphere_z","to","plot","a","sphere",".","Create","the","arrays","sphere_x",",","sphere_y",",","sphere_z","of","values","to","plot","the","wireframe","of","a","sphere",".","Their","shape","is","(","n_meridians",",","n_circles_latitude",")","."]
docstr: Set axis.
docstr_tok: ["Set","axis","."]
code: def set_ax(ax=None):
      """Set axis."""
      if ax is None:
          ax = plt.subplot(111, projection="3d")
  
      ax_s = AX_SCALE
      plt.setp(
          ax,
          xlim=(-ax_s, ax_s),
          ylim=(-ax_s, ax_s),
          zlim=(-ax_s, ax_s),
          xlabel="X",
          ylabel="Y",
          zlabel="Z",
      )
      ax.set_box_aspect([1.0, 1.0, 1.0])
      return ax
  
file_path: geomstats/geomstats/visualization/hypersphere.py
imports: import matplotlib.pyplot
  from mpl_toolkits.mplot3d import Axes3D
  import geomstats.backend
  from geomstats.geometry.hypersphere import Hypersphere
label_desc: Use image node_id 2 for calling the Sphere obj's underlying member method code with example usage: obj.set_ax(ax) and returns: ax