freq.na {questionr}

Generate frequency table of missing values.

Description

Generate a frequency table of missing values as raw counts and percentages.

Usage

freq.na(data, ...)

Arguments

data

either a vector or a data frame object

...

if x is a data frame, the names of the variables to examine or keywords to search for such variables. See lookfor for more details.

Value

The result is an object of class data.frame.

See Also

table, is.na

Examples

data(hdv2003)
## Examine a single vector.
freq.na(hdv2003$qualif)
## Examine a data frame.
freq.na(hdv2003)
## Examine several variables.
freq.na(hdv2003, "nivetud", "trav.satisf")
## To see only variables with the most number of missing values
head(freq.na(hdv2003))