Insert standard missing values.
Standardizes missing values in variable data.
If the DataVariables option is supplied, only the indicated variables are standardized.
indicator is passed along to
standardizeMissing when it is called on each
of the data variables in turn. The same indicator is used for all
variables. You can mix and match indicator types by just passing in
mixed indicator types in a cell array; indicators that don’t match the
type of the column they are operating on are just ignored.
Returns a table with same variable names and types as obj, but with variable values standardized.