size of scatter plot points matplotlib code example

Example: matplotlib units of scatter size

star = MarkerStyle('*')
bbox = star.get_path().transformed(star.get_transform()).get_extents()
star_unit_width = bbox.width
star_unit_height = bbox.height
plt.scatter(0, -1, marker='s', s=(xscale*desired_data_width/star_unit_width)**2)