setcolsnull

a character vector of column names to be deleted

delete

a character vector of column names to keep; 
the rest will be removed; <code>keep</code> overrides <code>delete</code>

keep

logical; if <code>TRUE</code>, also does <code>setcolorder</code> using
<code>keep</code>

colorder

logical; if <code>TRUE</code>, does not cause an error if any variable
name in <code>keep</code> or <code>delete</code> is missing; <code>soft = FALSE</code> useful 
for programming sometimes

soft

Deletes columns in a <code>data.table</code> conveniently.
May only delete columns that are found silently. Sometimes useful in e.g.
<code>on.exit</code> expressions.

Enables computation of various epidemiological statistics where the use of population data such as population counts and hazards is required.
                 Relatively high computation speed achieved by using data.table.

setcolsnull: Delete `data.table` columns if there

Description

Usage

Arguments