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I'm trying to fit a Lorentzian function with more than Imaginary part of Silicon, but the curve_fit function it not working properly, not fitting any peaks with this message.
D:\anacode\lib\site-packages\scipy\optimize\minpack.py:447: RuntimeWarning: Number of calls to function has reached maxfev = 3400. warnings.warn(errors[info][0], RuntimeWarning)
How can I fit it?
I used code of this answer: How can I fit a good Lorentzian on python using scipy.optimize.curve_fit?

import numpy as np
import matplotlib.pyplot as plt
from scipy.optimize import curve_fit
from scipy.optimize import leastsq

 def lorentzian( w, w0, w_p, gam ):
     return w * gam * pow(w_p,2) / ( (w*gam)**2 + ( pow(w,2) - pow(w0,2) )**2)

 def multi_lorentz( x, params ):
     off = params[0]
     paramsRest = params[1:]
     assert not ( len( paramsRest ) % 3 ) #0,1,2가 아니면  assert error 발생
     return off + sum( [ lorentzian( x, *paramsRest[ i : i+3 ] ) for i in range( 0, len( paramsRest ), 3 ) ] )

 def res_multi_lorentz( params, xData, yData ):
     diff = [ multi_lorentz( x, params ) - y for x, y in zip( xData, yData ) ]
     return diff
 xData, yData = np.loadtxt('E2_Silicon.dat', unpack=True )
 xData=xData[2400:]
 yData=yData[2400:]
 generalWidth = 1
 yDataLoc = yData
 startValues = [ min( yData ) ]
 counter = 0
 while max( yDataLoc ) - min( yDataLoc ) >1:
       counter += 1
       if counter > 20: ### max 20 peak...emergency break to avoid infinite loop
          break
       maxP = np.argmax( yDataLoc )
       maxY = yData[ maxP ]
       x0 = xData[ maxP ]
       startValues += [ x0, np.sqrt(maxY*x0), generalWidth ]
       popt, ier = leastsq( res_multi_lorentz, startValues, args=( xData, yData ) )
       yDataLoc = [ y - multi_lorentz( x, popt ) for x,y in zip( xData, yData ) ]
       #if ier == 6, find 6 set of lorentzian parameters 

 print(popt)
 testData = [ multi_lorentz(x, popt ) for x in xData ]
 fig = plt.figure()
 ax = fig.add_subplot( 1, 1, 1 )
 ax.plot( xData, yData )
 ax.plot( xData, testData )
 plt.show()

MyData: https://drive.google.com/file/d/19lSJKn6ZTeZlLVgii794hQZg2AKgbTBK/view?usp=sharing

leebyeoungju
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0 Answers0