Fitting Models Exercise 2

Imports



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%matplotlib inline
import matplotlib.pyplot as plt
import numpy as np
import scipy.optimize as opt

For this problem you are given a raw dataset in the file decay_osc.npz. This file contains three arrays:

Your job is to fit the following model to this data:

$$ y(t) = A e^{-\lambda t} \cos{\omega t + \delta} $$

First, import the data using NumPy and make an appropriately styled error bar plot of the raw data.



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# YOUR CODE HERE
raise NotImplementedError()



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assert True # leave this to grade the data import and raw data plot

Now, using curve_fit to fit this model and determine the estimates and uncertainties for the parameters:

Print the parameters estimates and uncertainties.
Plot the raw and best fit model.
You will likely have to pass an initial guess to curve_fit to get a good fit.
Treat the uncertainties in $y$ as absolute errors by passing absolute_sigma=True.



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# YOUR CODE HERE
raise NotImplementedError()



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assert True # leave this cell for grading the fit; should include a plot and printout of the parameters+errors