python带有图例的散点图

rng = np.random.RandomState(0)
for marker in ['o', '.', ',', 'x', '+', 'v', '^', '<', '>', 's', 'd']:
    plt.plot(rng.rand(5), rng.rand(5), marker,
             label="marker='{0}'".format(marker))
plt.legend(numpoints=1)
plt.xlim(0, 1.8)

转自：https://jakevdp.github.io/PythonDataScienceHandbook/04.02-simple-scatter-plots.html