Python | Numpy NP . polyFromroots()方法
原文:https://www . geeksforgeeks . org/python-numpy-NP-polyromroots-method/
**np.polyfromroots()**
方法用于生成给定根的多项式级数。
语法:
np.polyfromroots(roots)
参数: 根:【array _ like】输入包含根的序列。返回:【n 数组】多项式级数系数的一维数组。
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)
Output:
[-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)
Output:
[-120\. 274\. -225\. 85\. -15\. 1.]