R/methods.R

In stemangiola/tidySCE: Brings SingleCellExperiment to the Tidyverse

#' @importFrom methods getMethod
setMethod(
    f="show",
    signature="SingleCellExperiment",
    definition=function(object) {
        opt <- getOption("restore_SingleCellExperiment_show", default=FALSE)
        if (isTRUE(opt)) {
            f <- getMethod(
                f="show",
                signature="SummarizedExperiment",
                where=asNamespace(ns="SummarizedExperiment"))
            f(object=object)
        } else { print(object) }
    }
)

setClass("tidySingleCellExperiment", contains="SingleCellExperiment")

#' @name join_features
#' @rdname join_features
#' @inherit ttservice::join_features
#' @aliases join_features,SingleCellExperiment-method
#'
#' @return A `tidySingleCellExperiment` object
#'   containing information for the specified features.
#'
#' @examples
#' data(pbmc_small)
#' pbmc_small %>% join_features(
#'   features=c("HLA-DRA", "LYZ"))
#'
#' @importFrom magrittr "%>%"
#' @importFrom dplyr contains
#' @importFrom dplyr everything
#' @importFrom ttservice join_features
#' @importFrom stringr str_c
#' @importFrom stringr str_subset
#' @export
setMethod("join_features", "SingleCellExperiment", function(.data,
    features=NULL, all=FALSE, exclude_zeros=FALSE, shape="long", ...) {
    # CRAN Note
    .cell <- NULL
    .feature <- NULL

    # Shape is long
    if (shape == "long") {
      
        # Suppress generic data frame creation message produced by left_join
        suppressMessages({
            .data <-
                .data %>%
                    left_join(
                        by=c_(.data)$name,
                        get_abundance_sc_long(
                            .data=.data,
                            features=features,
                            all=all,
                            exclude_zeros=exclude_zeros)) %>%
                    select(!!c_(.data)$symbol, .feature,
                        contains(".abundance"), everything())
        })
      
        # Provide data frame creation and abundance column message
        if (any(class(.data) == "tbl_df")) {
            
            abundance_columns <-
                .data %>%
                colnames() %>%
                stringr::str_subset('.abundance_')
            
            message(stringr::str_c("tidySingleCellExperiment says: join_features produces",
                " duplicate cell names to accomadate the long data format. For this reason, a data", 
                " frame is returned for independent data analysis. Assay feature abundance is", 
                " appended as ", 
                stringr::str_flatten_comma(abundance_columns, last = " and "), "."
            ))
        }
      
        .data
        
    # Shape if wide
    } else {
        .data  %>%
            left_join(
                by=c_(.data)$name,
                get_abundance_sc_wide(
                    .data=.data,
                    features=features,
                    all=all, ...))
    }
})

#' @name tidy
#' @rdname tidy
#' @title tidy for `SingleCellExperiment`
#'
#' @param object A `SingleCellExperiment` object.
#' @return A `tidySingleCellExperiment` object.
#'
#' @examples
#' data(pbmc_small)
#' pbmc_small
#'
#' @export
tidy <- function(object) {
    UseMethod("tidy", object)
}

#' @rdname tidy
#' @importFrom lifecycle deprecate_warn
#' @export
tidy.SingleCellExperiment <- function(object) {

    # DEPRECATE
    deprecate_warn(
        when="1.1.1",
        what="tidy()",
        details="tidySingleCellExperiment says: tidy() is not needed anymore.")

    return(object)
}

#' @name aggregate_cells
#' @rdname aggregate_cells
#' @inherit ttservice::aggregate_cells
#' @aliases aggregate_cells,SingleCellExperiment-method
#'
#' @examples
#' data(pbmc_small)
#' pbmc_small_pseudo_bulk <- pbmc_small |>
#'   aggregate_cells(c(groups, ident), assays="counts")
#'
#' @importFrom rlang enquo
#' @importFrom magrittr "%>%"
#' @importFrom tibble enframe
#' @importFrom Matrix rowSums
#' @importFrom ttservice aggregate_cells
#' @importFrom SummarizedExperiment assays assays<- assayNames
#' @importFrom S4Vectors split
#' @importFrom stringr str_remove
#' @importFrom dplyr group_split
#'
#'
#' @export
setMethod("aggregate_cells", "SingleCellExperiment", function(.data,
    .sample=NULL, slot="data", assays=NULL,
    aggregation_function=Matrix::rowSums,
    ...) {

    # Fix NOTEs
    feature <- NULL
    .sample <- enquo(.sample)

    # Subset only wanted assays
    if (!is.null(assays)) {
        assays(.data) <- assays(.data)[assays]
    }


    grouping_factor =
      .data |>
      colData() |>
      as_tibble() |>
      select(!!.sample) |>
      suppressMessages() |>
      unite("my_id_to_split_by___", !!.sample, sep = "___") |>
      pull(my_id_to_split_by___) |>
      as.factor()

    list_count_cells = table(grouping_factor) |> as.list()

    # New method
    list_assays =
      .data |>
      assays() |>
      as.list() |>
      map(~ .x |> splitColData(grouping_factor)) |>
      unlist(recursive=FALSE)

    list_assays =
      list_assays |>
      map2(names(list_assays), ~ {
        # Get counts
        .x %>%
          aggregation_function(na.rm=TRUE) %>%
          enframe(
            name =".feature",
            value="x") %>% # sprintf("%s", .y)) %>%

          # In case we don't have rownames
          mutate(.feature=as.character(.feature))
      }) |>
      enframe(name = ".sample") |>

      # Clean groups
      mutate(assay_name = assayNames(!!.data) |> rep(each=length(levels(grouping_factor)))) |>
      mutate(.sample = .sample |> str_remove(assay_name) |> str_remove("\\.")) |>
      group_split(.sample) |>
      map(~ .x |>  unnest(value) |> pivot_wider(names_from = assay_name, values_from = x) ) |>

      # Add cell count
      map2(
        list_count_cells,
        ~ .x |> mutate(.aggregated_cells = .y)
      )


    do.call(rbind, list_assays) |>

        left_join(
          .data |>
            colData() |>
            as_tibble() |>
            subset(!!.sample) |>
            unite("my_id_to_split_by___", !!.sample, remove=FALSE, sep = "___"),
            by= join_by(".sample" == "my_id_to_split_by___")
        ) |>

        as_SummarizedExperiment(
            .sample=.sample,
            .transcript=.feature,
            .abundance=!!as.symbol(names(.data@assays)))
})