R/utils.R

In spdesign: Designing Stated Preference Experiments

#' Repeat rows
#'
#' Repeats each row in the matrix or data frame 'x' a number of times equal to
#' 'times'.
#'
#' @param x A matrix or data frame
#' @param times An integer indicating the number of times to repeat the
#' row/column
#'
#' @returns A matrix or data.frame depending on type of the input
#'
#' @examples
#' test_matrix <- matrix(runif(12), 4)
#' rep_rows(test_matrix, 2)
#'
#' @export
rep_rows <- function(x, times) {
  if (!(is.data.frame(x) || is.matrix(x))) {
    stop("'x' must be a data.frame or matrix")
  }

  return(
    x[rep(seq_len(nrow(x)), each = times), , drop = FALSE]
  )
}

#' Repeat columns
#'
#' Repeats each column of the matrix or data frame 'x' a number of times equal
#' to 'times'.
#'
#' @inheritParams rep_rows
#'
#' @returns A matrix or data.frame depending on the type of the input
#'
#' @examples
#' test_matrix <- matrix(runif(12), 4)
#' rep_cols(test_matrix, 2)
#'
#' @export
rep_cols <- function(x, times) {
  if (!(is.data.frame(x) || is.matrix(x))) {
    stop("'x' must be a data.frame or matrix")
  }

  return(
    x[, rep(seq_len(ncol(x)), each = times), drop = FALSE]
  )
}

#' Match names as whole words
#'
#' Creates regular expressions that match names as whole words, so that e.g.
#' x1 does not match x10, b_x1 or alt1_x1. Names in the utility functions only
#' contain letters, digits and underscores.
#'
#' @param name A character vector of names
#'
#' @return A character vector of regular expressions
as_whole_word <- function(name) {
  paste0("\\b", name, "\\b")
}