我想用curve_fit拟合一条复杂曲线,并求出方程中的三个参数,但是运行后程序报错如下
TypeError: 'numpy.float64' object is not callable
代码如下,哪里出错了,我没有找到变量和函数名冲突
- import matplotlib.pyplot as plt
- import numpy as np
- from scipy.optimize import curve_fit
-
- # a,b,c是需要求出来的三个参数,D,z,ee全都是已知的。
- def dfin(x, a, b, c):
- return ((a*z**b-30.0)(1.0-np.exp(-np.log(2.0*(x/ee)**c))))
-
-
- D = 30.0
- z = 1.31*10**21
- ee = 0.0016*D**0.2709*z**0.1147
- # 给出x、y对应坐标
- x = [1.29, 1.24, 1.11, 0.97, 0.82, 0.68, 1.07, 0.86, 0.64, 0.52]
- x = np.array(x)
- num = [15.7, 15.0, 18.2, 18.7, 21.1, 24.5, 15.7, 21.2, 24.8, 31.7]
- y = np.array(num)
-
- # 非线性最小二乘法拟合
- popt, pcov = curve_fit(dfin, x, y)
- # 获取popt里面拟合系数
- print(popt)
- a = popt[0]
- b = popt[1]
- c = popt[2]
- yvals = dfin(x, a, b, c)
- print('系数a:', a)
- print('系数b:', b)
- print('系数c:', c)
- print('系数yvals:', yvals)
-
- # 绘图
- plot1 = plt.plot(x, y, 's', label='original values')
- plot2 = plt.plot(x, yvals, 'r', label='polyfit values')
- plt.xlabel('x')
- plt.ylabel('y')
- plt.legend(loc=4)
- plt.title('curve_fit')
- plt.show()
-