Python中的 numpy.polyder()

numpy.polyder()方法计算具有指定阶数的多项式的导数。

Syntax :numpy.polyder(p, m)
Parameters :
p : [array_like or poly1D]the polynomial coefficients are given in decreasing order of powers. If the second parameter (root) is set to True then array values are the roots of the polynomial equation.
For example : poly1d(3, 2, 6) = 3x² + 2x + 6

m : [int, optional] Order of differentiation.

Return: Derivative of polynomial.

代码：解释 polyder() 的Python代码

# Python code explaining 
# numpy.polyder()
    
# importing libraries
import numpy as np
import pandas as pd
  
# Constructing polynomial 
p1 = np.poly1d([1, 2]) 
p2 = np.poly1d([4, 9, 5, 4]) 
    
print ("P1 : ", p1) 
print ("\n p2 : \n", p2) 

# Solve for x = 2 
print ("\n\np1 at x = 2 : ", p1(2)) 
print ("p2 at x = 2 : ", p2(2)) 

a = np.polyder(p1, 1)
b = np.polyder(p2, 1)
print ("\n\nUsing polyder")
print ("p1 derivative of order = 1 : \n", a) 
print ("p2 derivative of order = 1 : \n", b) 

a = np.polyder(p1, 2)
b = np.polyder(p2, 2)
print ("\n\nUsing polyder")
print ("p1 derivative of order = 2 : ", a) 
print ("p2 derivative of order = 2 : ", b)