numpy.poly(seq)：給出多項式根的序列，此函數返回多項式的係數。
參數：
Seq:sequence of roots of the polynomial roots, or a matrix of roots.返回： 1D array having coefficients of the polynomial from the highest degree to the lowest one.
c[0] * x**(N) + c[1] * x**(N-1) + … + c[N-1] * x + c[N] where c[0] always equals 1.
# Python code explaining
# numpy.poly()
# importing libraries
import numpy as np
# Giving the roots
seq_1 = (2, 1, 0)
a = np.poly(seq_1)
print ("Coefficients of the polynomial:", a)
# Constructing polynomial
p1 = np.poly1d(a)
print ("\nAbove polynomial = \n", p1) 輸出：
Coefficients of the polynomial: [ 1. -3. 2. 0.]
Above polynomial =
3 2
1 x - 3 x + 2 x
代碼2：
# Python code explaining
# numpy.poly()
# importing libraries
import numpy as np
# Giving the roots
seq_2 = (2, 1, 0, 2, 4, 2)
b = np.poly(seq_2)
print ("Coefficients of the polynomial:", b)
# Constructing polynomial
p2 = np.poly1d(b)
print ("\nAbove polynomial = \n", p2) 輸出：
Coefficients of the polynomial: [ 1. -11. 46. -92. 88. -32. 0.]
Above polynomial =
6 5 4 3 2
1 x - 11 x + 46 x - 92 x + 88 x - 32 x
相關用法
注：本文由純淨天空篩選整理自Mohit Gupta_OMG 大神的英文原創作品 numpy.poly() in Python。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。