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One-Dimensional
- Line
- Polynomial
- Gaussian peak
- Lorentzian peak
- Exponential with X offset constant
- Double Exponential with X offset constant
- Exponential
- Double Exponential
- Sin
- Hill Equation
- Sigmoid
- Power
- Lognormal
Two-Dimensional
- Gaussian
- Polynomial
All built-in nonlinear fit functions feature automatic initial guess generation.
Override automatic initial guesses with your own.
Hold any fit coefficient. For instance, hold constant term in line fit to fit a line through the origin or any other y-intercept.
![Built-in Fit Function Illustrations](/sites/www.wavemetrics.com/files/images-imported/LittleFunctionPics_3.png)
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