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嗨我试图产生一个适合我的三个指数衰减。产生令人满意的结果我没有成功。这是我得到:http://i.imgur.com/Nx44wsS.jpgPython指数衰减curve_fit给我一个线性拟合
任何帮助,非常感谢。我的代码如下。
import pylab as plb
import matplotlib.pyplot as plt
import matplotlib.axes as ax
import scipy as sp
from scipy.optimize import curve_fit
from matplotlib import rc
rc('font',**{'family':'sans-serif','sans-serif':['Helvetica']})
## for Palatino and other serif fonts use:
#rc('font',**{'family':'serif','serif':['Palatino']})
rc('text', usetex=True)
data = plb.loadtxt('data.csv',skiprows=2)
yp = data[:,4]
yr = data[:,5]
yl = data[:,6]
x = data[:,0]
def func(x,a,b,c):
return a*np.exp(-b*x) + c
popt, pcov = curve_fit(func, x, yl,maxfev=20000)
a = popt[0]
b = popt[1]
c = popt[2]
print a
print b
print c
print func(x,a,b,c)
xf = np.linspace(0,70,100)
yf = a*np.exp(-b*x) + c
plt.clf()
plt.plot(x,yf,'r-', label="Fitted Curve")
plt.plot(x,func(x,*popt))
plt.plot(x,yp,'bo',label='Polished')
plt.plot(x,yr,'ro',label='Rough')
plt.plot(x,yl,'go',label='Lacquered')
plt.legend()
plt.ylabel("Temperature (K)")
plt.xlabel("Time (min)")
plt.show()
非常感谢,这很好。我现在看到初始参数的重要性。 –