R/freq.R

In dtdibaba/StatTools: Biostatistical tools to produce clean data analysis results with StatTools

#' @title Frequency table for a single variable

#' @description This is a frequency table function which prints the frequency
#'  and related row percentage for a given categorical variable.The function
#'   creates the count and related row percentages for a given
#' categorical variables and allows naming the header.
#' Provide the distinct level names as a list.
#' @param var  A categorical variable to be analyzed
#' @param row Row name for the output
#' @param colnames Level names for the categorical variable
#' @examples
#' # Example
#' set.seed(1234)
#' letter = list(sample(letters[1:5], 20, replace = TRUE))
#' freq(letter, row = c("Letter"), colnames = c("A", "B", "C", "D", "E"))
#' @export
freq <- function(var, row, colnames) {
    tab1 <- table(var)
    tab = round(100 * prop.table(tab1), 1)
    ncols = dim(tab1)
    for (i in 1:ncols) {
        tab[i] <- paste0(tab1[[i]], '(', tab[[i]], "%", ')')
    }
    prop <- matrix((c(dimnames(tab[1])[[1]], tab)), byrow = 1, ncol = ncols, nrow = 1, dimnames = NULL)
    dimnames(prop) <- list(row, colnames) # The Freq is added as row names.
    prop <- noquote(prop)
    return(prop)
}