# Uses of Interface
ij.measure.UserFunction

Packages that use UserFunction
Package
Description
ij.measure

## Uses of UserFunction in ij.measure

Classes in ij.measure that implement UserFunction
Modifier and Type
Class
Description
`class`
`CurveFitter`
Curve fitting class based on the Simplex method in the Minimizer class Notes on fitting polynomial functions: (i) The range of x values should not be too far from 0, especially for higher-order polynomials.
Methods in ij.measure with parameters of type UserFunction
Modifier and Type
Method
Description
`void`
CurveFitter.`doCustomFit(UserFunction userFunction, int numParams, String formula, double[] initialParams, double[] initialParamVariations, boolean showSettings)`
Fit a function defined in a user plugin implementing the UserFunction interface Use getStatus() and/or getStatusString() to see whether fitting was (probably) successful and getParams() to access the result.
`void`
Minimizer.`setFunction(UserFunction userFunction, int numParams)`
Set the the target function, i.e.