| #' Add footnote |
| #' |
| #' @description Add footnote to your favorite kable output. So far this function |
| #' only works when you define \code{format} in your kable function or in the |
| #' global knitr option \code{knitr.table.format}. In latex, we are using the |
| #' \code{threeparttable} package so you need to import this package in your |
| #' \code{YAML} header. |
| #' |
| #' @param input The direct output of your \code{kable} function or your last |
| #' \code{kableExtra} function. |
| #' @param label A vector of footnotes you want to add. You don't need to add |
| #' notations in your notes. |
| #' @param notation You can select the format of your footnote notation from |
| #' `number`, `alphabet` and `symbol`. |
| #' @param threeparttable Boolean value indicating if a |
| #' \href{https://www.ctan.org/pkg/threeparttable}{threeparttable} scheme should |
| #' be used. |
| #' |
| #' @examples x <- knitr::kable(head(mtcars), "html") |
| #' add_footnote(x, c("footnote 1", "footnote 2"), notation = "symbol") |
| #' |
| #' @export |
| add_footnote <- function(input, label = NULL, |
| notation = "alphabet", |
| threeparttable = FALSE) { |
| if (is.null(label)) return(input) |
| |
| if (notation == "alphabet") { |
| notation <- getOption("kable_footnote_notation", "alphabet") |
| } |
| if (!threeparttable) { |
| threeparttable <- getOption("kable_footnote_threeparttable", FALSE) |
| } |
| |
| notation <- match.arg(notation, c("alphabet", "number", "symbol")) |
| if (notation == "symbol") { |
| notation <- paste0(notation, ".", attr(input, "format")) |
| } |
| |
| table_info <- NULL |
| |
| ids.ops <- read.csv(system.file("symbol_index.csv", package = "kableExtra")) |
| ids <- ids.ops[, notation] |
| ids.intable <- gsub("\\*", "\\\\*", ids) |
| |
| #count the number of items in label and intable notation |
| count.label <- length(label) |
| count.intablenote <- sum(str_count(input, "\\[note\\]")) |
| if (count.intablenote != 0 & count.label != count.intablenote) { |
| warning(paste("You entered", count.label, "labels but you put", |
| count.intablenote, "[note] in your table.")) |
| } |
| |
| export <- input |
| |
| # Find out if there are any extra in-table notations needed to be corrected |
| extra.notation <- unique(as.numeric( |
| str_extract( |
| str_extract_all( |
| paste0(export, collapse = ""), "\\[note[0-9]{1,2}\\]" |
| )[[1]], |
| "[0-9]{1,2}"))) |
| |
| # Pandoc --------------------------- |
| # Footnote solution for markdown and pandoc. It is not perfect as |
| # markdown doesn't support complex table formats but this solution |
| # should be able to satisfy people who don't want to spend extra |
| # time to define their `kable` format. |
| if (!attr(input, "format") %in% c("html", "latex")) { |
| # In table notation |
| if (count.intablenote != 0) { |
| for (i in 1:count.intablenote) { |
| replace_note <- paste0("^", ids.intable[i], "^", |
| paste0(rep(" ", 4 - ceiling(i/5)), collapse = "")) |
| |
| export[which(str_detect(export, "\\[note\\]"))[1]] <- |
| sub("\\[note\\]", replace_note, |
| export[which(str_detect(export, "\\[note\\]"))[1]]) |
| } |
| } |
| # Fix extra in table notation |
| for (i in extra.notation) { |
| export <- gsub(paste0("\\[note", i, "\\]"), |
| paste0("^", ids.intable[i], "^", |
| paste0(rep(" ", 4 - ceiling(i/5)), collapse = "")), |
| export) |
| } |
| |
| export[length(export) + 1] <- "" |
| export[length(export) + 1] <- "__Note:__" |
| export[length(export) + 1] <- paste0( |
| paste0("^", ids[1:length(label)], "^ ", label), collapse = " " |
| ) |
| } |
| |
| # LaTeX Tables -------------------------------- |
| if (attr(input, "format") == "latex") { |
| # Clean the entry for labels |
| label <- escape_latex(label) |
| label <- gsub("\\\\", "\\\\\\\\", label) |
| |
| export <- enc2utf8(export) |
| table_info <- magic_mirror(input) |
| if (table_info$tabular == "longtable") { |
| if (notation != "number") { |
| warning("Notation is set to 'number' and other formats are not supported.") |
| notation <- "number" |
| } |
| # If longtable is used, then use page footnote instead of threeparttable |
| # as it makes more sense to see the footnote at the bottom of page if |
| # table is longer than one page. |
| if (threeparttable == T) { |
| warning("Threeparttable does not support longtable.") |
| threeparttable = F |
| } |
| |
| # Longtable doesn't support footnote in caption directly. |
| # See http://tex.stackexchange.com/questions/50151/footnotes-in-longtable-captions |
| |
| count.in.caption.note <- 0 |
| if (!is.na(table_info$caption)) { |
| count.in.caption.note <- str_count(table_info$caption, "\\[note\\]") |
| } |
| if (count.in.caption.note != 0) { |
| caption.footnote <- paste0("\\\\addtocounter{footnote}{-", |
| count.in.caption.note, "}") |
| for (i in 1:count.in.caption.note) { |
| export <- sub("\\[note\\]", "\\\\protect\\\\footnotemark ", export) |
| caption.footnote <- paste0( |
| caption.footnote, "\n\\\\stepcounter{footnote}\\\\footnotetext{", |
| label[i], "}") |
| } |
| |
| if (str_detect(export, "\\\\toprule")) { |
| export <- sub("\\\\toprule", |
| paste0("\\\\toprule\n", caption.footnote), export) |
| } else { |
| export <- sub("\\\\hline", |
| paste0("\\\\hline\n", caption.footnote), export) |
| } |
| } |
| for (i in (count.in.caption.note + 1):count.intablenote) { |
| export <- sub("\\[note\\]", |
| paste0("\\\\footnote[", i, "]{", label[i], "}"), export) |
| } |
| for (i in extra.notation) { |
| export <- gsub(paste0("\\[note", i, "\\]"), |
| paste0("\\\\footnotemark[", i, "]"), |
| export) |
| } |
| } else { |
| # Replace in-table notation with appropriate symbol |
| for (i in 1:count.intablenote) { |
| export <- sub("\\[note\\]", |
| paste0("\\\\textsuperscript{", ids.intable[i], "}"), |
| export) |
| } |
| |
| # Fix extra in table notation |
| for (i in extra.notation) { |
| export <- gsub(paste0("\\[note", i, "\\]"), |
| paste0("\\\\textsuperscript{", ids.intable[i], "}"), |
| export) |
| } |
| if (threeparttable == T) { |
| # generate footer with appropriate symbol |
| usepackage_latex("threeparttable") |
| footer <- "" |
| for (i in 1:count.label) { |
| footer <- paste0(footer,"\\\\item [", ids[i], "] ", label[i], "\n") |
| } |
| |
| if (grepl("\\\\caption\\{.*?\\}", export)) { |
| export <- sub("\\\\caption\\{", |
| "\\\\begin{threeparttable}\n\\\\caption{", |
| export) |
| } else { |
| export <- sub("\\\\begin\\{tabular\\}", |
| "\\\\begin{threeparttable}\n\\\\begin{tabular}", |
| export) |
| } |
| export <- gsub( |
| "\\\\end\\{tabular\\}", |
| paste0("\\\\end{tabular}\n\\\\begin{tablenotes}\n\\\\small\n", |
| footer, "\\\\end{tablenotes}\n\\\\end{threeparttable}"), |
| export) |
| } else { |
| table.width <- max(nchar( |
| str_replace_all( |
| str_replace_all(table_info$contents, "\\[note\\]", ""), |
| "\\[note[0-9]{1,2}\\]", ""))) + 2 * (table_info$ncol - 1) |
| footer <- "" |
| for (i in 1:count.label) { |
| label.wrap <- strwrap(label[i], table.width) |
| footer <- paste0(footer, "\\\\multicolumn{", table_info$ncol, |
| "}{l}{\\\\textsuperscript{", ids[i], "} ", |
| label.wrap[1], "}\\\\\\\\\n") |
| if (length(label.wrap) > 1) { |
| for (j in 2:length(label.wrap)) { |
| footer <- paste0(footer, "\\\\multicolumn{", table_info$ncol, |
| "}{l}{", label.wrap[j], "}\\\\\\\\\n") |
| } |
| } |
| } |
| export <- gsub("\\\\end\\{tabular\\}", |
| paste0(footer, "\\\\end{tabular}"), |
| export) |
| } |
| } |
| } |
| |
| # HTML Tables ------------------- |
| if (attr(input, "format") == "html") { |
| # Clean the entry for labels |
| table_info <- magic_mirror(input) |
| label <- escape_html(label) |
| # Replace in-table notation with appropriate symbol |
| for (i in 1:count.intablenote) { |
| export <- sub("\\[note\\]", |
| paste0("<sup>", ids.intable[i], "</sup>"), |
| export) |
| } |
| |
| # Fix extra in table notation |
| for (i in extra.notation) { |
| export <- gsub(paste0("\\[note", i, "\\]"), |
| paste0("<sup>", ids.intable[i], "</sup>"), |
| export) |
| } |
| |
| # Build footer |
| footer <- "<tfoot>\n" |
| for (i in 1:count.label) { |
| footer <- paste0(footer, "<tr>\n<td style = 'padding: 0; border:0;' ", |
| "colspan='100%'><sup>", ids[i],"</sup> ", |
| label[i], "</td>\n</tr>\n") |
| } |
| footer <- paste0(footer, "</tfoot>\n") |
| |
| # Paste footer to the table |
| export[1] <- gsub("</tbody>\n", paste0("</tbody>\n", footer), export[1]) |
| } |
| attr(export, "kable_meta") <- table_info |
| return(export) |
| } |