[英]Why can't scipy.optimize.curve_fit fit my data using a numpy.sinc function?
[英]Using scipy.optimize.curve_fit I can't fit V*cos(ω*t) function correctly
我已经从 python 中的 function 创建了数据,所以我认为适合需要完美,但不是我不知道为什么
import matplotlib.pyplot as plt
import numpy as np
from scipy.optimize import curve_fit
def fun(offset, V, f, phi):
return V * np.cos(2*np.pi*f * x + phi) + offset
xData = np.arange(0, 1, 0.005) #time
f = 2 #frequency
yData = 5 * np.cos(2*np.pi*f * x)
popt, pcov = curve_fit(fun, xData, yData, p0=[1, 1, 1])
print(popt)
plt.scatter(xData, yData, label="data")
plt.plot(xData, fun(x, *popt), label="fit")
plt.legend(loc = "upper right")
plt.show()
有多个问题,包括您的 function 定义和初步猜测。 这有效:
import matplotlib.pyplot as plt
import numpy as np
from scipy.optimize import curve_fit
def fun(xData, offset, V, f, phi):
return V * np.cos(2*np.pi*f * xData + phi) + offset
xData = np.arange(0, 1, 0.005) #time
f = 2 #frequency
yData = 5 * np.cos(2*np.pi*f * xData)
popt, pcov = curve_fit(fun, xData, yData, p0=[0, 6, 2, 1])
print(popt)
plt.scatter(xData, yData, label="data", c='k')
plt.plot(xData, fun(xData, *popt), label="fit", c='r')
plt.legend(loc = "upper right")
plt.show()
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.