Question

我正在研究一种使用牛顿法求解方程的代码。它只能找到答案之一（根）。所以我尝试用x-answer除以方程，找到新方程的答案，这是初始方程的另一个答案，但是我得到了一个错误：

Traceback (most recent call last):
  File "C:\Users\fathollahy\Desktop\w.py", line 26, in <module>
    rt = f/WE
TypeError: unsupported operand type(s) for /: 'function' and 'Add'

这是我的代码：

from sympy import *
from random import randrange
x = Symbol('x')
T = input('Eqution: ')
f = eval(T)
f_prime = f.diff(x)
f = lambdify(x, f)
f_prime = lambdify(x, f_prime)
x = randrange(100)
print('attempts:')

while f(x) != 0:
  D = f_prime(x)
  F = f(x)
  Q = F/D
  x = x-Q
  print(x)
else:
  QW = x
  print("answer:")
  print(QW)
  input()

x = Symbol('x')
WE = x-QW
rt = f/WE
rt_prime = rt.diff(x)
rt = lambdify(x, rt)
rt_prime = lambdify(x, rt_prime)
x = randrange(100)
print('attempts:')

while rt(x) != 0:
  D = rt_prime(x)
  F = rt(x)
  Q = F/D
  x = x-Q
  print(x)
else:
  QW = x
  print("answer:")
  print(QW)
  input()

这段代码只能找到一个答案，并且效果很好（除了牛顿方法的缺点，如x ^（1/3）：

from sympy import *
from random import randrange
x = Symbol('x')
T = input('Eqution: ')
f = eval(T)
f_prime = f.diff(x)
f = lambdify(x, f)
f_prime = lambdify(x, f_prime)
x = randrange(100)
print('attempts:')

while f(x) != 0:
  D = f_prime(x)
  F = f(x)
  Q = F/D
  x = x-Q
  print(x)
else:
  QW = x
  print("answer:")
  print(QW)
  input()

TypeError：/：“功能”和“添加”不支持的操作数类型

0 个答案: