This package provides an R-commander “plug-in” for the core functions in the doBy package, which helps with computing groupwise statistics.

CRAN page: http://cran.r-project.org/web/packages/RcmdrPlugin.doBy/

Source: https://github.com/jon-lee/RcmdrPlugin.doBy

**Examples using mtcars dataset:**

Computing the mean displacement (disp) for each group of cars grouped by number of cylinders (cyl):

Systematic sample of 10% of each combination of number of cylinders (cyl) and number of gears (gear):