Use missing value information to report the effects of an na.action
.
naprint(x, …)
An object produced by an na.action
function.
further arguments passed to or from other methods.
A character string providing information on missing values, for example the number.
This is a generic function, and the exact information differs by
method. naprint.omit
reports the number of rows omitted:
naprint.default
reports an empty string.