R/apply_row.R

In martinctc/surveytools: Useful Support Functions for Survey Analysis

#' @title Apply a function rowwise, selecting variables with dplyr::select() syntax
#'
#' @description
#' `apply_row()` is a wrapper around `apply()` and `select()`,
#' applying a function rowwise, and selecting variables with dplyr::select() syntax.
#' This makes code slightly less verbose for rowwise operations.
#'
#' @param x Data frame or tibble to pass through.
#' @param select_helpers Select variables using dplyr::select() syntax
#' @param FUN Function to be applied to selected columns
#' @param ... Additional arguments to the function.
#' 
#' @examples
#' \dontrun{
#' library(tidyverse)
#' iris %>% mutate(Sepal_Sum = apply_row(.,select_helpers = contains("Sepal"), sum, na.rm = TRUE))
#' iris %>% mutate(Sepal_Sum = apply_row(.,c("Sepal.Length","Petal.Width"), function(x) sum(x > 1))) 
#' 
#' Can use a character vector to select columns
#' petal_str <- c("Petal.Length", "Petal.Width")
#' iris %>% mutate(Any_Petal = apply_row(., petal_str, function(x) any(x > 1)))
#' }
#' 
#' 
#' @export

apply_row <- function(x, select_helpers = everything(), FUN, ...){
  apply(select(x, select_helpers), 1, FUN, ...)
}