R/latex.R

In hwriterPlus: hwriterPlus: Extending the hwriter Package

as.latex <- function(x, label = NULL,
                     inline = ifelse(is.null(label), TRUE, FALSE),
                     count = ifelse(is.null(label), FALSE, TRUE))
{
  out <- list(alt = x, inline = inline, count = count, label = label)
  class(out) <- "latex"
  return(out)
}


hwriteLatex <- function(ltx, page = NULL,
                        table.attributes = NULL,
                        tr.attributes = NULL,
                        td.attributes = NULL, ...)
{
    ## cat is used to write to files, deal with output to standard output
    if (is.null(page)) page = ""
    ## Note: no append argument as it could ONLY be happened to work...
    ## count: add a (#)
    ## label: add before: Equation (#): label
    if (! is(ltx, "latex")) ltx <- as.latex(ltx)
    if (ltx$inline){
        ## inline: directly there in the text (can't be counted or labeled)
        cat(paste("\\(", ltx$alt,"\\)", sep = ""),
            file = page, append = TRUE, sep = " ")
    } else {
        ## not inline: own living space (will be within a table to center it)
        if (ltx$count) {
            ## update counter hwriterEquation
            ## hwriterEquation <<- hwriterEquation + 1
            eqnNum <- get("hwriterEquation", .hwriterGlobalEnv)
            eqnNum <- eqnNum + 1
            assign("hwriterEquation", eqnNum, .hwriterGlobalEnv)
            ## deal with label
            if (is.null(ltx$label)){
                ## hwriterEquationList[hwriterEquation] <<-
                ##     paste("eq:", hwriterEquation, sep = "")
                eqnLabel <- paste("eq:", eqnNum, sep = "")
            } else {
                ## hwriterEquationList[hwriterEquation] <<-
                ##     paste("eq:", ltx$label, sep = "")
                eqnLabel <- paste("eq:", ltx$label, sep = "")
            }
            eqnList <- get("hwriterEquationList", .hwriterGlobalEnv)
            eqnList[eqnNum] <- eqnLabel
            assign("hwriterEquationList", eqnList, .hwriterGlobalEnv)
            ## write out equation as table with equation number
            if (is.null(table.attributes)){
                table.attributes <- "border = '0' width = '90%'"
            }
            if (is.null(td.attributes)){
                td.attributes <- c("width = '50'",
                                   "align = 'center'",
                                   "align = 'right' width = '50'")

            }
            cat(paste("\n<br /><center><table ",
                      table.attributes, "><tr ",
                      tr.attributes, "><td ",
                      td.attributes[1], ">&nbsp;</td><td ",
                      td.attributes[2], ">\\[",
                      ltx$alt, "\\]</td><td ",
                      td.attributes[3], " id = '",
                      eqnLabel,
                      "'>(", eqnNum,
                      ")</td></tr></table></center><br />",
                      sep = ""),
                file = page, append = TRUE)
        } else {
            if (is.null(table.attributes)){
                table.attributes <- "border = '0'"
            }
            cat(paste("<br /><center><table ",
                      table.attributes, "><tr ",
                      tr.attributes, "><td align = 'center'>\\[",
                      ltx$alt, "\\]</td></tr></table></center><br />",
                      sep = ""),
                file = page, append = TRUE)
        }
    }
}