The data frame containing the data to be summarised in the
pivot table.
rows
A character vector of variable names to be plotted on the rows of
the pivot table, or "=" to specify the position of the calculations.
columns
A character vector of variable names to be plotted on the
columns of the pivot table, or "=" to specify the position of the
calculations.
calculations
One or more summary calculations to use to calculate the
values of the cells in the pivot table.
...
Additional arguments, currently format, formats, totals,
argumentCheckMode, caption and/or label. See the Latex output vignette for
a description of caption and label.