我有两组数据(比如x和y(。我想拟合y=x-a-btanh[(x-a(/b(]的tanh曲线(双曲正切(，并返回a和b参数。我尝试了以下代码，但出现错误，TypeError:"numpy.ufunc"对象不可下标。此外，我想知道以下函数是否是拟合tanh曲线的正确方法。谢谢
from scipy.optimize import curve_fit
import numpy as np
import matplotlib as plt
x=[799.0,872.0,882.0,986.0,722.0,479.0,747.0,510.0,1012.0,1114.0,801.0,662.0,853.0,878.0,779.0,987.0,707.0,756.0,730.0,523.0,802.0,1068.0,780.0,927.0,923.0,790.0,852.0,580.0,730.0,924.0,762.0,662.0,927.0,828.0,866.0,951.0,949.0,740.0,677.0,704.0,798.0,791.0,761.0]
y=[27.64,110.75,139.34,66.02,26.66,5.29,11.75,3.81,64.07,286.23,57.23,43.61,18.68,55.4,65.97,206.51,16.32,19.25,10.98,3.12,15.41,122.89,62.43,112.18,34.86,46.59,48.96,3.69,11.3,49.92,18.96,6.57,32.74,35.76,46.35,115.04,131.46,46.63,26.25,4.55,9.21,36.32,11.47]
def myfunc(x,a,b):
return x-a-b*np.tanh[(x-a)/b]
popt, pcov = curve_fit(myfunc, x, y)
plt.plot(x, myfunc(x, *popt))
问题就在这里：np.tanh[(x-a)/b]
这可能是数学符号，但它不是有效的python语法。
函数是用括号()调用的。所以应该是：np.tanh((x-a)/b)