R/methods-subsetPerSample.R

In roryk/bcbioSinglecell: Single-Cell RNA-Seq Utilities

#' Subset Per Sample
#'
#' @name subsetPerSample
#' @family Data Functions
#' @author Michael Steinbaugh
#'
#' @inheritParams general
#' @param minCells Minimum number of cells required per sample.
#' @param assignAndSave Assign and save the individual datasets.
#' @param envir Environment where to assign the subsets. Only applicable when
#'   `assignAndSave = TRUE`.
#' @param dir Output directory. Only applicable when `assignAndSave = TRUE`.
#'
#' @return
#' - `assignAndSave = FALSE`: Per sample objects in a `list`.
#' - `assignAndSave = TRUE`: Subset file paths.
#'
#' @examples
#' # bcbioSingleCell ====
#' # List mode (default)
#' list <- subsetPerSample(indrops_small, assignAndSave = FALSE)
#' names(list)
#'
#' # Assign and save mode (useful for large datasets)
#' subsetPerSample(
#'     object = indrops_small,
#'     assignAndSave = TRUE,
#'     envir = parent.frame(),
#'     dir = "subsetPerSample"
#' )
#' list.files("subsetPerSample")
#'
#' # Clean up
#' unlink("subsetPerSample", recursive = TRUE)
NULL



# Methods ======================================================================
#' @rdname subsetPerSample
#' @export
setMethod(
    "subsetPerSample",
    signature("bcbioSingleCell"),
    function(
        object,
        minCells = 200L,
        assignAndSave = FALSE,
        envir = parent.frame(),
        dir = "."
    ) {
        assertIsAnImplicitInteger(minCells)
        assert_all_are_positive(minCells)
        assert_is_environment(envir)
        dir <- initializeDirectory(dir)
        samples <- levels(cell2sample(object))

        # Return objects or file paths
        return <- lapply(
            X = samples,
            FUN = function(sampleID) {
                subset <- selectSamples(object, sampleID = sampleID)
                # Skip if subset doesn't have enough cells
                if (ncol(subset) < minCells) {
                    warning(paste(sampleID, "didn't pass minimum cell cutoff"))
                    return(NULL)
                }
                if (isTRUE(assignAndSave)) {
                    assignAndSaveData(
                        name = sampleID,
                        object = subset,
                        dir = dir
                    )
                } else {
                    subset
                }
            }
        )
        names(return) <- samples
        return <- Filter(Negate(is.null), return)

        if (isTRUE(assignAndSave)) {
            # File paths
            names <- names(return)
            return <- unlist(return)
            return <- normalizePath(return, winslash = "/", mustWork = TRUE)
            names(return) <- names
            invisible(return)
        } else {
            # Individual objects
            return
        }
    }
)