代码错误一元操作数类型错误-：'str'

Question

我正在编写一个在 S 曲线上产生噪声的代码，该代码有效，因为我用真实值尝试过它，它工作得很好。

我试图通过创建两个用户可以决定的输入来使其更复杂，这将是噪声和曲线的陡度。

这是我的代码：

import numpy as np
import matplotlib.pyplot as plt

def sigmoid(z):
    return 1 / (1 + np.exp(-z)) #Function for the S-curve

noise=input('Please, insert here a number that will define how big the noise of the curve will be (the bigger the number, the bigger the noise.): ')
steepness=input('Please, insert here a number that will define the steepness of the curve (The bigger the number, the steeper the steep): ')

x = np.arange(-steepness, steepness, (2*steepness)/1000)  # x values
n = noise * np.random.random(x.shape) - 0.1 # noise for each value of the sigmoid
y = sigmoid(x) + n  # S-curve plus noise
print(y)
plt.plot(x, y, marker='*')
plt.xlabel('X-axis')
plt.ylabel('Y-axis')
plt.title('S-curve with noise')
plt.show()

但是使用这段代码我有两个错误...

第一个是这个：TypeError: bad operand type for unary -: 'str'

第二个是这个：ufunc 'multiply' 没有包含签名匹配类型的循环 (dtype(' dtype('

另一个没有输入的代码可以正常工作是这个：

import numpy as np
import matplotlib.pyplot as plt

def sigmoid(z):
    return 1 / (1 + np.exp(-z)) #Function for the S-curve

x = np.arange(-5, 5, 0.01)  # x values
n = 0.2 * np.random.random(x.shape) - 0.1 # noise for each value of the sigmoid
y = sigmoid(x) + n  # S-curve plus noise
print(y)
plt.plot(x, y, marker='*')
plt.xlabel('X-axis')
plt.ylabel('Y-axis')
plt.title('S-curve with noise')
plt.show()

你能帮我找出问题所在吗？

Answer 1

使用float将输入转换为浮点数：

noise=float(input('Please, insert here a number that will define how big the noise of the curve will be (the bigger the number, the bigger the noise.): '))
steepness=float(input('Please, insert here a number that will define the steepness of the curve (The bigger the number, the steeper the steep): '))

如果不包括这个，Python 会认为变量是字符串，而不是数字。