# LINFIT

## Purpose: The LINFIT class performs a linear least-squares fit of *y* and *x* data arrays.

The data arrays are normally extracted from one of the Explain CURVE type objects. The fit is to an equation of the form *y* = m*x* + b. The fit results in estimates for m, b, a residual and a goodness-of-fit parameter.

The most common use of an Explain LINFIT object is in polarization resistance calculations. The data arrays are chosen to include a corrosion potential (where the current changes sign). If the *x* array is current and the *y* array is potential, the slope m is the polarization resistance with units of Ω. The LINFIT class can also be used for other purposes.

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