Contour plot(s) of a fitted linear model in ggplot2

## Arguments

- rsm_model
Model of class "rsm"

- formula
A formula, or a list of formulas

- decode
This has an effect only if x is an rsm object or other model object that supports coded.data. In such cases, if decode is TRUE, the coordinate axes are transformed to their decoded values.

- n_columns
number of columns for grid layout. Default is 2

- text_size
size of text for labelled contour lines. Default is 3

- bins
Number of contour bins. Overridden by binwidth

- ...
Other arguments passed on to contour(). For help with more arguments see ?rsm::contour.lm