print object dimensions and size in R

obj_size.R

obj_size <- function(obj, units = 'Mb') {
    dimensions <- dim(obj)
    data.frame(
        rows = format(dimensions[1], big.mark = ","),
        columns = format(dimensions[2], big.mark = ","),
        size = format(object.size(obj), units = units, big.mark = ",")
    )
}