Linear is via @johnhenry/math's Statistics.linearRegression/correlation. Nonlinear fits any custom model you type (e.g. a*exp(b*x)) via Numerical.levenbergMarquardt -- a damped Gauss-Newton fit starting from the initial guess shown beside each parameter, with the fitted curve resampled and redrawn over the current view.
| x | y | |
|---|---|---|
y = 1.9900x + 0.0500 (r = 0.9987, r² = 0.9973)