R/format_numbers.R

In GegznaV/BioStat: Routines for Basic (Bio)Statistics

# TODO:
# 1) add parameter `skip` - for columns to skip.
# 2) add parameter `include` - for the only columns to format.
# 3) check and warn if `skip`  and `include` contain at least one common column name.
# 4) add value digits = "auto" to automatically choose number of digits to round to.
# 5) check if negalive values of "digits" are accepted. (patikrinti, ar galima naudoti neigiamus skaicius, ar su jais apvalina teisingai.)
#


# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Format Numbers in Each Column of a Dataframe
#
# data - data frame
# digits -
# the desired number of digits after the decimal point (format = "f") or significant digits (format = "g", = "e" or = "fg"). \cr
# Either one integer or a vector of inegers for each column.
#
# format - either one value or a vector of values for each column.
#       Each value Will be passed to `fun` separately.
#
# ... - to be passed to `fun`
# fun - formatting function to be applied. Default is `formatC`
#




#' Format values of numeric columns in a dataframe.
#'
#' Function formats numeric columns only.
#' Other classes are left intact.
#'
#'
#' @param data A data frame.
#'
#' @param digits (numeric or `NA`) a desired number of digits after the decimal point (if `format = "f"`) or a number of significant digits (`format = "g"`, `= "e"` or `= "fg"`). \cr
#' Either one integer (to set the same formatting for all columns) or a vector of inegers (to set formatting for each column separately).\cr
#' Use `NA` to leave column unformatted.
#'
#' @param format (character) `"f"`, `"g"`, `"e"`, `"fg"`. Either one value or a vector of values for each column.
#'   Each value will be passed to `fun` separately.\cr
#'   `"f"` gives numbers in the usual `xxx.xxx` format;\cr
#'   `"e"` and `"E"` give `n.ddde+nn` or `n.dddE+nn` (scientific format);\cr
#'   `"g"` and `"G"` put number into scientific format only if it saves space to do so.\cr
#'   `"fg"` uses fixed format as `"f"`, but digits as the minimum number of significant digits. This can lead to quite long result strings
#'
#' @param fun A function that does the formatting.
#' Default is [base::formatC()].
#' @param ... Other parameters to be passed to `fun`.
#'
#' @export
#'
#' @examples
#' library(biostat)
#' DATA <- head(iris)
#'
#' # The same rounding for each column
#' format_numbers(DATA, 2)
#'
#' # Different rounding for different columns
#' format_numbers(DATA, c(2, 2, 3, 3, NA))
#'
#' # Use `NA` to leave a column unformatted
#' format_numbers(DATA, c(4, NA, 3, NA, NA))
format_numbers <- function(data,
                           digits = 3,
                           format = "f",
                           fun = formatC,
                           ...) {
  # Apply the recycling of values
  digits <- if (is_named(digits)) {
    adjust_named_vector(digits, data)
  } else {
    adjust_vector_length(digits, data)
  }

  format <- if (is_named(format)) {
    adjust_named_vector(format, data)
  } else {
    adjust_vector_length(format, data)
  }


  # Apply the formatting
  for (i in seq_along(data)) {
    if (!is.numeric(data[[i]])) next
    if (is.na(digits[i])) next
    data[[i]] <-
      fun(data[[i]], digits = digits[i], format = format[i], ...)
  }
  # Output:
  data
}