gzahn:

vlookup <- function(this, data, key, value) {
  m <- match(this, data[[key]])
  data[[value]][m]
}

#function to assign letter grades in BIOL 1620 ####
biol1620_letter_grades = function(x){   # give data frame object
  Grade = c()

  for(i in 1:length(row.names(x))){

    if(x$Final.Points[i] >= 600){
      Grade[i] <- "A"
    }
    if(x$Final.Points[i] %in% c(540:599)){
      Grade[i] <- "B"
    }
    if(x$Final.Points[i] %in% c(480:539)){
      Grade[i] <- "C"
    }
    if(x$Final.Points[i] %in% c(400:479)){
      Grade[i] <- "D"
    }
    if(x$Final.Points[i] < 400){
      Grade[i] <- "E"
    }
  }
  assign("letter.grades", Grade, envir = .GlobalEnv)
}

# For data course grading ####

data_course_letter_grades = function(x, a.cutoff = 700, b.cutoff = c(640,699), c.cutoff = c(560,639), d.cutoff = c(480,559)){   # give data frame object that has "Final.Points" column.
  Grade = c()

  for(i in 1:length(row.names(x))){

    if(x$Final.Points[i] >= a.cutoff){
      Grade[i] <- "A"
    }
    if(x$Final.Points[i] %in% c(b.cutoff[1]:b.cutoff[2])){
      Grade[i] <- "B"
    }
    if(x$Final.Points[i] %in% c(c.cutoff[1]:c.cutoff[2])){
      Grade[i] <- "C"
    }
    if(x$Final.Points[i] %in% c(d.cutoff[1]:d.cutoff[2])){
      Grade[i] <- "D"
    }
    if(x$Final.Points[i] < d.cutoff[1]){
      Grade[i] <- "E"
    }
  }
  assign("letter.grades", Grade, envir = .GlobalEnv)
}

#' A Modified Heatmap Function ####
#'
#' This function is identical to the heatmap() function, but puts row labels on the left side
#' @param x numeric matrix
#' @keywords heatmap
#' @export
#' @examples
#' heatmap_left()

heatmap_left <- function (x, Rowv = NULL, Colv = if (symm) "Rowv" else NULL,
                          distfun = dist, hclustfun = hclust, reorderfun = function(d,
                                                                                    w) reorder(d, w), add.expr, symm = FALSE, revC = identical(Colv,
                                                                                                                                               "Rowv"), scale = c("row", "column", "none"), na.rm = TRUE,
                          margins = c(5, 5), ColSideColors, RowSideColors, cexRow = 0.2 +
                            1/log10(nr), cexCol = 0.2 + 1/log10(nc), labRow = NULL,
                          labCol = NULL, main = NULL, xlab = NULL, ylab = NULL, keep.dendro = FALSE,
                          verbose = getOption("verbose"), ...)
{
  scale <- if (symm && missing(scale))
    "none"
  else match.arg(scale)
  if (length(di <- dim(x)) != 2 || !is.numeric(x))
    stop("'x' must be a numeric matrix")
  nr <- di[1L]
  nc <- di[2L]
  if (nr <= 1 || nc <= 1)
    stop("'x' must have at least 2 rows and 2 columns")
  if (!is.numeric(margins) || length(margins) != 2L)
    stop("'margins' must be a numeric vector of length 2")
  doRdend <- !identical(Rowv, NA)
  doCdend <- !identical(Colv, NA)
  if (!doRdend && identical(Colv, "Rowv"))
    doCdend <- FALSE
  if (is.null(Rowv))
    Rowv <- rowMeans(x, na.rm = na.rm)
  if (is.null(Colv))
    Colv <- colMeans(x, na.rm = na.rm)
  if (doRdend) {
    if (inherits(Rowv, "dendrogram"))
      ddr <- Rowv
    else {
      hcr <- hclustfun(distfun(x))
      ddr <- as.dendrogram(hcr)
      if (!is.logical(Rowv) || Rowv)
        ddr <- reorderfun(ddr, Rowv)
    }
    if (nr != length(rowInd <- order.dendrogram(ddr)))
      stop("row dendrogram ordering gave index of wrong length")
  }
  else rowInd <- 1L:nr
  if (doCdend) {
    if (inherits(Colv, "dendrogram"))
      ddc <- Colv
    else if (identical(Colv, "Rowv")) {
      if (nr != nc)
        stop("Colv = \"Rowv\" but nrow(x) != ncol(x)")
      ddc <- ddr
    }
    else {
      hcc <- hclustfun(distfun(if (symm)
        x
        else t(x)))
      ddc <- as.dendrogram(hcc)
      if (!is.logical(Colv) || Colv)
        ddc <- reorderfun(ddc, Colv)
    }
    if (nc != length(colInd <- order.dendrogram(ddc)))
      stop("column dendrogram ordering gave index of wrong length")
  }
  else colInd <- 1L:nc
  x <- x[rowInd, colInd]
  labRow <- if (is.null(labRow))
    if (is.null(rownames(x)))
      (1L:nr)[rowInd]
  else rownames(x)
  else labRow[rowInd]
  labCol <- if (is.null(labCol))
    if (is.null(colnames(x)))
      (1L:nc)[colInd]
  else colnames(x)
  else labCol[colInd]
  if (scale == "row") {
    x <- sweep(x, 1L, rowMeans(x, na.rm = na.rm), check.margin = FALSE)
    sx <- apply(x, 1L, sd, na.rm = na.rm)
    x <- sweep(x, 1L, sx, "/", check.margin = FALSE)
  }
  else if (scale == "column") {
    x <- sweep(x, 2L, colMeans(x, na.rm = na.rm), check.margin = FALSE)
    sx <- apply(x, 2L, sd, na.rm = na.rm)
    x <- sweep(x, 2L, sx, "/", check.margin = FALSE)
  }
  lmat <- rbind(c(NA, 3), 2:1)
  lwid <- c(if (doRdend) 1 else 0.05, 4)
  lhei <- c((if (doCdend) 1 else 0.05) + if (!is.null(main)) 0.2 else 0,
            4)
  if (!missing(ColSideColors)) {
    if (!is.character(ColSideColors) || length(ColSideColors) !=
        nc)
      stop("'ColSideColors' must be a character vector of length ncol(x)")
    lmat <- rbind(lmat[1, ] + 1, c(NA, 1), lmat[2, ] + 1)
    lhei <- c(lhei[1L], 0.2, lhei[2L])
  }
  if (!missing(RowSideColors)) {
    if (!is.character(RowSideColors) || length(RowSideColors) !=
        nr)
      stop("'RowSideColors' must be a character vector of length nrow(x)")
    lmat <- cbind(lmat[, 1] + 1, c(rep(NA, nrow(lmat) - 1),
                                   1), lmat[, 2] + 1)
    lwid <- c(lwid[1L], 0.2, lwid[2L])
  }
  lmat[is.na(lmat)] <- 0
  if (verbose) {
    cat("layout: widths = ", lwid, ", heights = ", lhei,
        "; lmat=\n")
    print(lmat)
  }
  dev.hold()
  on.exit(dev.flush())
  op <- par(no.readonly = TRUE)
  on.exit(par(op), add = TRUE)
  layout(lmat, widths = lwid, heights = lhei, respect = TRUE)
  if (!missing(RowSideColors)) {
    par(mar = c(margins[1L], 0, 0, 0.5))
    image(rbind(if (revC)
      nr:1L
      else 1L:nr), col = RowSideColors[rowInd], axes = FALSE)
  }
  if (!missing(ColSideColors)) {
    par(mar = c(0.5, 0, 0, margins[2L]))
    image(cbind(1L:nc), col = ColSideColors[colInd], axes = FALSE)
  }
  par(mar = c(margins[1L], 0, 0, margins[2L]))
  if (!symm || scale != "none")
    x <- t(x)
  if (revC) {
    iy <- nr:1
    if (doRdend)
      ddr <- rev(ddr)
    x <- x[, iy]
  }
  else iy <- 1L:nr
  image(1L:nc, 1L:nr, x, xlim = 0.5 + c(0, nc), ylim = 0.5 +
          c(0, nr), axes = FALSE, xlab = "", ylab = "", ...)
  axis(1, 1L:nc, labels = labCol, las = 2, line = -0.5, tick = 0,
       cex.axis = cexCol)
  if (!is.null(xlab))
    mtext(xlab, side = 1, line = margins[1L] - 1.25)
  axis(2, iy, labels = labRow, las = 2, line = -0.5, tick = 0,
       cex.axis = cexRow)
  if (!is.null(ylab))
    mtext(ylab, side = 4, line = margins[2L] - 1.25)
  if (!missing(add.expr))
    eval.parent(substitute(add.expr))
  par(mar = c(margins[1L], 0, 0, 0))
  if (doRdend)
    plot(ddr, horiz = TRUE, axes = FALSE, yaxs = "i", leaflab = "none")
  else frame()
  par(mar = c(0, 0, if (!is.null(main)) 1 else 0, margins[2L]))
  if (doCdend)
    plot(ddc, axes = FALSE, xaxs = "i", leaflab = "none")
  else if (!is.null(main))
    frame()
  if (!is.null(main)) {
    par(xpd = NA)
    title(main, cex.main = 1.5 * op[["cex.main"]])
  }
  invisible(list(rowInd = rowInd, colInd = colInd, Rowv = if (keep.dendro &&
                                                              doRdend) ddr, Colv = if (keep.dendro && doCdend) ddc))
}