descriptive_tables.R

# function to make table of descriptive statistics
# rows are column names, columns are the descriptives (mean, min etc.)

descriptive_tab <- function(df, cols, round_digits = 2) {
  
  # cols needs to be a vector
  # cols <- c('col1', 'col2', 'col3')
  
  tab <- data.frame(
    t(
      apply(
        df[, cols],
        MARGIN = 2,
        function (x) c(
          mean = round(mean(x, na.rm = TRUE), round_digits),
          median = round(median(x, na.rm = TRUE), round_digits),
          min = round(min(x, na.rm = TRUE), round_digits),
          max = round(max(x, na.rm = TRUE), round_digits),
          standard_deviation = round(sd(x, na.rm = TRUE), round_digits)
        )
      )
    )
  )
  return(tab)
}

# example use with Iris dataset
iris_cols <- c("Sepal.Length", "Sepal.Width", 
               "Petal.Length", "Petal.Width")
iris_stats <- descriptive_tab(
  df = iris, 
  cols = iris_cols, 
  round_digits = 3
)
iris_stats