Python 如何强制限定小数点位数

c = 1.264871331241212
print("%.3f"%c)

import numpy as np
a = np.random.random(3)
print('before set precision: \n',a)
 
np.set_printoptions(precision=3, suppress=True)
print('after set precision: \n',a)
 
np.set_printoptions(formatter={'float': '{: 0.3f}'.format})
print('after set formatter: \n',a)

before set options: 
 [ 0.05856348 0.5400039 0.70000603]
after set precision: 
 [ 0.059 0.54 0.7]
after set formatter: 
 [ 0.059 0.540 0.700]