R/rbindFill.R

In MsCoreUtils: Core Utils for Mass Spectrometry Data

#' @title Combine R Objects by Row
#'
#' @description
#' This function combines instances of `matrix`, `data.frame` or `DataFrame`
#' objects into a single instance adding eventually missing columns (filling
#' them with `NA`s).
#'
#' @param ... 2 or more: `matrix`, `data.frame` or `DataFrame`.
#'
#' @return Depending on the input a single `matrix`, `data.frame` or
#' `DataFrame`.
#'
#' @note
#' `rbindFill` might not work if one of the columns contains S4 classes.
#'
#'
#' @author Johannes Rainer, Sebastian Gibb
#'
#' @family helper functions for developers
#' @importMethodsFrom S4Vectors cbind nrow rownames colnames
#' @importFrom methods as
#' @export
#' @examples
#' ## Combine matrices
#' a <- matrix(1:9, nrow = 3, ncol = 3)
#' colnames(a) <- c("a", "b", "c")
#' b <- matrix(1:12, nrow = 3, ncol = 4)
#' colnames(b) <- c("b", "a", "d", "e")
#' rbindFill(a, b)
#' rbindFill(b, a, b)
rbindFill <- function(...) {
    l <- list(...)

    if (length(l) == 1L && is.list(l[[1L]]))
        l <- l[[1L]]

    cnms <- c("matrix", "data.frame", "DataFrame", "DFrame")

    if (inherits(l, cnms))  # just one single object given as input, do nothing
        return(l)

    cls <- vapply(l, inherits, integer(length(cnms)), what = cnms, which = TRUE)
    rownames(cls) <- cnms

    if (any(!as.logical(colSums(cls))))
        stop("'rbindFill' just works for ", paste(cls, collapse = ", "))

    ## convert matrix to data.frame for easier and equal subsetting and class
    ## determination
    isMatrix <- as.logical(cls["matrix",])
    l[isMatrix] <- lapply(l[isMatrix], as.data.frame)

    allcl <- unlist(
        lapply(l, function(ll) {
            vapply1c(ll, function(lll)class(lll)[1L], USE.NAMES = TRUE)
        })
    )
    allnms <- unique(names(allcl))
    allcl <- allcl[allnms]

    for (i in seq(along=l)) {
        diffcn <- setdiff(allnms, names(l[[i]]))
        if (length(diffcn))
            l[[i]][, diffcn] <- lapply(allcl[diffcn], as, object = NA)
    }
    r <- do.call(rbind, l)

    ## if we had just matrices as input we need to convert our temporary
    ## data.frame back to a matrix
    if (all(isMatrix))
        r <- as.matrix(r)
    r
}

## helper function to allow lapply(..., as, ...) in rbindFill
setAs("logical", "factor", function(from, to) factor(from))