Python Numpy np.polyfromroots()方法

np.polyfromroots() 方法用于生成具有给定根数的多项式数列。

语法: np.polyfromroots(roots)
参数:
roots : [array_like] 包含根的输入序列。

返回： [ndarray] 多项式数列的系数的一维数组。

代码#1：

# Python program explaining
# numpy.polyfromroots() method 
    
# importing numpy as np  
# and numpy.polynomial.polynomial module as geek 
import numpy as np 
import numpy.polynomial.polynomial as geek
    
# Input roots
  
roots = (2, 4, 8) 
     
# using np.polyfromroots() method 
res = geek.polyfromroots(roots) 
  
# Resulting polynomial series coefficient
print (res)

输出:

[-64.  56. -14.   1.]

代码#2：

# Python program explaining
# numpy.polyfromroots() method 
    
# importing numpy as np  
# and numpy.polynomial.polynomial module as geek 
import numpy as np 
import numpy.polynomial.polynomial as geek
    
# Input roots
s = (1, 2, 3, 4, 5) 
  
    
# using np.polyfromroots() method 
res = geek.polyfromroots(s) 
  
# Resulting polynomial series coefficient
print (res)

输出: