Prepare and clean a data.table for quadrilogy

Source: R/helpers.R

Standardizes the names of the columns, set the keys, compute the frequencies

clean_and_count(dt, unit_from, measurement_from, frequency_from)

Arguments

dt

`data.table` containing measurements, either coders or standard.
unit_from

Name of the column containing the unit ID
measurement_from

Name of the column containing the measurements
frequency_from

(Optional) Name of the column containing the frequencies, *if* the data is in the "aggregated".

Value