Functions > Data Analysis > Curve Fitting > Example: Exponential Regression
  
Example: Exponential Regression
Use the expfit function to perform exponential regression. Exponential functions are common everywhere there is a process that decays or grows to a steady state, such as radioactive decay, the transient response of an RC circuit, or the displacement of an overdamped spring.
1. Define an appropriate dataset.
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2. Call the expfit function to find the parameters of an exponential fit.
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The parameters fit the following exponential equation:
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3. Plot the data and the exponential fit.
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The expfit function is unusual among nonlinear fitting functions because it does not require a guess value, although you may supply one if you do not like the results you are getting from the internal guess routine. The internal routine starts from fitting a line to the y values.