R/utility_functions.R

In stephanGit/reporters: Utility Functions to render Datatables, Figures, ... neatly in a report

#' display tibble conditional on output format
#'
#' utility function that displays a dataframe as
#' pandoc.table or datatable
#'
#' @param df tibble to be printed
#' @param caption caption for table
#' @param output char: pdf/default
#' @param page_length nr. of rows to display
#' @param col_select_enable logical: enable col-select-button
#' @param colnames colnames to be displayed
#' @param longtable logical defaults to TRUE
#' @param align alignment of columns
#' @param latex_options char-vector: passed to kableStyling
#' @param full_width table spans full width if true
#' @param modify_these_columns char-vector of col-names to be modified
#' @param column_widths width of the columns [cm] in pdf output
#'
#' @return markup for pandoc
#'
#' @export print_df
#'
#' @examples
#' library(tidyverse)
#' datasets::mtcars %>% print_df(caption = "mtcars", output = "pdf")
print_df <- function(
  df, #dataframe to be printed
  output = "default", # output to pdf or not
  caption = NULL,
  colnames,
  # options for datatable (html and notebook)
  page_length = 10,
  col_select_enable = FALSE,
  # options for kable (pdf)
  longtable = TRUE,
  align = NULL,
  # options for kableExtra::kable_styling
  latex_options = c("striped", "hold_position", "repeat_header"),
  full_width = TRUE,
  # options for kableExtra::column_spec
  modify_these_columns,
  column_widths
  ){

  Check <- ArgumentCheck::newArgCheck()

  if(missing(df)){
    ArgumentCheck::addMessage(
      msg = "df must not be missing",
      argcheck = Check
    )
  }

  if(any(missing(colnames))){
    colnames <- df %>% names
  }else{
    if(length(colnames) != length(names(df))){
      ArgumentCheck::addError(
        msg = "Nr. of columns in df an nr. of supplied columnnames must be equal",
        argcheck = Check
      )
    }
  }

  ArgumentCheck::finishArgCheck(Check)

  if(output == "pdf"){
    print_df <-
      df %>%
      knitr::kable(
        col.names = colnames,
        format = "latex",
        booktabs = TRUE,
        longtable = longtable,
        caption = caption,
        align = align,
        escape = FALSE
      ) %>%
      kableExtra::kable_styling(
        full_width = full_width,
        latex_options = latex_options
        )

    if(any(!missing(modify_these_columns))){
    print_df <-
      print_df %>%
      kableExtra::column_spec(
        column = which(colnames %in% c(modify_these_columns)),
        width = column_widths
      )
    }

    print_df
  }

  else{# output to notebook or html: make data-table interactive
    if(col_select_enable){
      df %>%
        DT::datatable(
          filter = "top", rownames = FALSE,
          extensions = c('ColReorder', 'Buttons'),
          options = list(pageLength = page_length, colReorder = TRUE, dom = 'Bfrtip', buttons = I('colvis')),
          caption = caption,
          colnames = colnames
        )
    }else{
      df %>%
        DT::datatable(
          filter = "top", rownames = FALSE,
          extensions = c('ColReorder'),
          options = list(pageLength = page_length, colReorder = TRUE),
          caption = caption,
          colnames = colnames
        )
    }

  }
}


#' returns string conditional on output format
#'
#' @param str string to be returned if output == "pdf"
#' @param output string specifing wheter output is pdf or default (html, nootbook...)
#'
#' @return string or Null
#' @export pdf_str
#'
pdf_str <- function(str, output = "pdf"){
  if(output == "pdf"){
    str
  }else{
    NULL
  }
}