freq: Frequency Table

Description

This function computes a frequency table with absolute and percentage frequencies for one or more than one variable.

Usage

freq(data, ..., print = c("no", "all", "perc", "v.perc"), freq = TRUE,
     split = FALSE, labels = TRUE, val.col = FALSE, round = 3, exclude = 15,
     digits = 2, as.na = NULL, write = NULL, append = TRUE, check = TRUE,
     output = TRUE)

Value

Returns an object of class misty.object, which is a list with following entries:

call: function call
type: type of analysis
data: data frame used for the current analysis
args: specification of function arguments
result: list with result tables, i.e., freq for absolute frequencies, perc for percentages, and v.perc for valid percentages

Arguments

data: a vector, factor, or data frame.
...: an expression indicating the variable names in data, e.g., freq(dat, x1, x2, x3). Note that the operators ., +, -, ~, :, ::, and ! can also be used to select variables, see 'Details' in the df.subset function.
print: a character string indicating which percentage(s) to be printed on the console, i.e., no percentages ("no"), all percentages ("all"), percentage frequencies ("print"), and valid percentage frequencies ("v.perc"). Default setting when specifying one variable is print = "all", while default setting when specifying more than one variable is print = "no" unless split = TRUE.
freq: logical: if TRUE (default), absolute frequencies will be shown on the console.
split: logical: if TRUE, output table is split by variables when specifying more than one variable in ....
labels: logical: if TRUE (default), labels for the factor levels will be used.
val.col: logical: if TRUE, values are shown in the columns, variables in the rows.
round: an integer value indicating the number of decimal places to be used for rounding numeric variables.
exclude: an integer value indicating the maximum number of unique values for variables to be included in the analysis when specifying more than one variable i.e., variables with the number of unique values exceeding exclude will be excluded from the analysis. It is also possible to specify exclude = FALSE to include all variables in the analysis.
digits: an integer value indicating the number of decimal places to be used for displaying percentages.
as.na: a numeric vector indicating user-defined missing values, i.e. these values are converted to NA before conducting the analysis.
write: a character string naming a file for writing the output into either a text file with file extension ".txt" (e.g., "Output.txt") or Excel file with file extension ".xlsx" (e.g., "Output.xlsx"). If the file name does not contain any file extension, an Excel file will be written.
append: logical: if TRUE (default), output will be appended to an existing text file with extension .txt specified in write, if FALSE existing text file will be overwritten.
check: logical: if TRUE (default), argument specification is checked.
output: logical: if TRUE (default), output is shown on the console.

Author

Takuya Yanagida takuya.yanagida@univie.ac.at

Details

By default, the function displays the absolute and percentage frequencies when specifying one variable, while the function displays only the absolute frequencies when more than one variable is specified. The function displays valid percentage frequencies only in the presence of missing values and excludes variables with all values missing from the analysis. Note that it is possible to mix numeric variables, factors, and character variables in the data frame specified in the argument data. By default, numeric variables are rounded to three digits before computing the frequency table.

References

Becker, R. A., Chambers, J. M., & Wilks, A. R. (1988). The New S Language. Wadsworth & Brooks/Cole.

Examples

Run this code

# Example 1: Frequency table for 'cyl'
freq(mtcars, cyl)

# Alternative specification without using the '...' argument
freq(mtcars$cyl)

# Example 2: Frequency table, values shown in columns
freq(mtcars, cyl, val.col = TRUE)

# Example 3: Frequency table, use 3 digit for displaying percentages
freq(mtcars, cyl, digits = 3)

# Example 4: Frequency table for 'cyl', 'gear', and 'carb'
freq(mtcars, cyl, gear, carb)

# Alternative specification without using the '...' argument
freq(mtcars[, c("cyl", "gear", "carb")])

# Example 5: Frequency table, with percentage frequencies
freq(mtcars, cyl, gear, carb, print = "all")

# Example 6: Frequency table, split output table
freq(mtcars, cyl, gear, carb, split = TRUE)

# Example 7: Frequency table, exclude variables with more than 5 unique values
freq(mtcars, exclude = 5)

if (FALSE) {
# Example 8a: Write Results into a text file
freq(mtcars, cyl, gear, carb, split = TRUE, write = "Frequencies.txt")

# Example 8b: Write Results into a Excel file
freq(mtcars, cyl, gear, carb, split = TRUE, write = "Frequencies.xlsx")}

Run the code above in your browser using DataLab

State of Data and AI Literacy Report 2025