R/Methods-MatrixGenotypeReader.R

In GWASTools: Tools for Genome Wide Association Studies

# Methods for MatrixGenotypeReader

MatrixGenotypeReader <- function(genotype=genotype, snpID=snpID, chromosome=chromosome, position=position, scanID=scanID, ...) {
  new("MatrixGenotypeReader", genotype=genotype, snpID=snpID, chromosome=chromosome, position=position, scanID=scanID, ...)
}

setValidity("MatrixGenotypeReader",
    function (object) {
      # check that dimensions and variables are as expected
      if (length(object@snpID) != nsnp(object)) {
        return("snpID has incorrect dimension")
      }
      if (length(object@chromosome) != nsnp(object)) {
        return("chromosome has incorrect dimension")
      }
      if (length(object@position) != nsnp(object)) {
        return("position has incorrect dimension")
      }
      if (length(object@scanID) != nscan(object)) {
        return("scanID has incorrect dimension")
      }
      if (!allequal(dim(object@genotype), c(nsnp(object), nscan(object)))) {
        return("genotype has incorrect dimensions")
      }

      TRUE
    })

# accessor methods
# index is logical or integer vector of indices to return
setMethod("getSnpID",
          signature(object="MatrixGenotypeReader"),
          function(object, index) {
            var <- object@snpID
            if (missing(index)) var else var[index]
          })

# char=TRUE to return character code
setMethod("getChromosome",
          signature(object="MatrixGenotypeReader"),
          function(object, index, char=FALSE) {
            var <- object@chromosome
            if (!missing(index)) var <- var[index]

            # convert to characters
            if (char) {
              # default is unknown code
              chromChar <- rep("U", length(var))
              autosome <- var %in% object@autosomeCode
              chromChar[autosome] <- as.character(var[autosome])
              xchrom <- var == object@XchromCode & !is.na(var)
              chromChar[xchrom] <- "X"
              ychrom <- var == object@YchromCode & !is.na(var)
              chromChar[ychrom] <- "Y"
              xychrom <- var == object@XYchromCode & !is.na(var)
              chromChar[xychrom] <- "XY"
              mchrom <- var == object@MchromCode & !is.na(var)
              chromChar[mchrom] <- "M"
              var <- chromChar
            }
            var
          })

setMethod("getPosition",
          signature(object="MatrixGenotypeReader"),
          function(object, index) {
            var <- object@position
            if (missing(index)) var else var[index]
          })

setMethod("getScanID",
          signature(object="MatrixGenotypeReader"),
          function(object, index) {
            var <- object@scanID
            if (missing(index)) var else var[index]
          })

setMethod("getGenotype",
          signature(object="MatrixGenotypeReader"),
          function(object, snp=c(1,-1), scan=c(1,-1), drop=TRUE, use.names=FALSE, transpose=FALSE) {
              snpstart <- snp[1]
              snpend <- ifelse(snp[2] == -1, nsnp(object), snp[1]+snp[2]-1)

              scanstart <- scan[1]
              scanend <- ifelse(scan[2] == -1, nscan(object), scan[1]+scan[2]-1)

              var <- object@genotype[snpstart:snpend, scanstart:scanend, drop=FALSE]
              if (use.names) {
                  dimnames(var) <- list(getSnpID(object)[snpstart:snpend],
                                        getScanID(object)[scanstart:scanend])
              }
              if (transpose) var <- t(var)
              if (drop) drop(var) else var
          })

setMethod("getGenotypeSelection",
          signature(object="MatrixGenotypeReader"),
          function(object, snp=NULL, scan=NULL, snpID=NULL, scanID=NULL, drop=TRUE, use.names=TRUE,
                   order=c("file", "selection"), transpose=FALSE) {

              order <- match.arg(order)

              if (!is.null(snpID)) {
                  if (!is.null(snp)) stop("cannot specify both snp and snpID")
                  snp <- match(snpID, getSnpID(object))
              }
              if (!is.null(scanID)) {
                  if (!is.null(scan)) stop("cannot specify both scan and scanID")
                  scan <- match(scanID, getScanID(object))
              }
              
              if (is.null(snp)) snp <- rep(TRUE, nsnp(object))
              if (is.null(scan)) scan <- rep(TRUE, nscan(object))

              if (order == "file") {
                  if (!is.logical(snp)) snp <- sort(snp)
                  if (!is.logical(scan)) scan <- sort(scan)
              }
              
              var <- object@genotype[snp, scan, drop=FALSE]
              if (use.names) {
                  dimnames(var) <- list(getSnpID(object)[snp],
                                        getScanID(object)[scan])
              }
              if (transpose) var <- t(var)
              if (drop) drop(var) else var
          })

setMethod("nsnp", "MatrixGenotypeReader",
          function(object) {
            nrow(object@genotype)
          })

setMethod("nscan", "MatrixGenotypeReader",
          function(object) {
            ncol(object@genotype)
          })

setMethod("autosomeCode", "MatrixGenotypeReader",
          function(object) {
            object@autosomeCode
          })

setMethod("XchromCode", "MatrixGenotypeReader",
          function(object) {
            object@XchromCode
          })

setMethod("YchromCode", "MatrixGenotypeReader",
          function(object) {
            object@YchromCode
          })

setMethod("XYchromCode", "MatrixGenotypeReader",
          function(object) {
            object@XYchromCode
          })

setMethod("MchromCode", "MatrixGenotypeReader",
          function(object) {
            object@MchromCode
          })

setMethod("show",
          signature(object="MatrixGenotypeReader"),
          function(object) {
            cat("An object of class", class(object), "\n")
            cat(paste("with", nscan(object), "scans and",
                      nsnp(object), "snps\n"))
          })