R/writeWig.R

In Repitools: Epigenomic tools

setGeneric("writeWig", function(rs, ...) standardGeneric("writeWig"))

setMethod("writeWig", "GRangesList",
    function(rs, seq.len = NULL, design=NULL, sample=20, drop.zero=TRUE, normalize=TRUE, verbose=TRUE)
{
    scipen <- getOption("scipen")
    options(scipen=100)
    if(!is.null(seq.len))
    {
        if (verbose) message("Extending the reads by ", seq.len,"bp\n", sep="" )
        rs <- endoapply(rs, resize, seq.len)
    }
    if (verbose) message("Creating coverage objects\n")
    rs.cov <- IRanges::lapply(rs, coverage)
    if (normalize) {
        if (verbose) message("Calculating normalisation counts\n")
        norm <- elementNROWS(rs)/1000000
    }
    if (is.null(design)) {
        if (verbose) message("Default design matrix\n")
        design <- matrix(0, nrow=length(rs), ncol=length(rs), dimnames=list(NULL, paste(names(rs), ".wig.gz", sep="")))
        for (i in 1:length(rs)) design[i,i] <- 1
    }
    for (i in 1:ncol(design)) {
        filename <- colnames(design)[i]
        if (verbose) message("Processing column",i,"of design matrix -",filename,"\n")
        f1 <- if (grepl("gz$",filename)) gzfile(filename, open="wt") else file(filename, open="wt")

        thisDes <- which(design[,i]!=0)
        thisMul <- design[thisDes,i]
        rs.this <- rs.cov[thisDes]		
        for (j in 1:length(rs.this[[1]])) {
            if (verbose) message(names(rs.this[[1]])[j]," ")
            #Write header for this chromosome
            writeLines(paste("variableStep chrom=", names(rs.this[[1]])[j]," span=", sample, sep=""), f1)
            #ensure all lanes being used have the same length
            chrMax <- max(sapply(rs.this, function(x) length(x[[j]])))
            for (k in 1:length(rs.this)) rs.this[[k]][[j]] <- c(rs.this[[k]][[j]], Rle(0, chrMax-length(rs.this[[k]][[j]]))) 
            bp <- 1:(length(rs.this[[1]][[j]]) %/% sample)*sample
            bp.score <- as.integer(rs.this[[1]][[j]][bp])/norm[thisDes[1]]*thisMul[1]
            if (length(thisDes)>1) for (k in 2:length(thisDes)) bp.score <- bp.score + as.integer(rs.this[[k]][[j]][bp])/norm[thisDes[k]]*thisMul[k]
            temp <- if (drop.zero) paste(bp[bp.score!=0], bp.score[bp.score!=0], sep="\t")
                    else paste(bp, bp.score, sep="\t")
            writeLines(temp, f1)
        }

        if (verbose) message("\n")
        close(f1)
    }
    options(scipen=scipen)
})

#setMethod("writeWig", "AffymetrixCelSet",
#    function(rs, design=NULL, log2.adj=TRUE, verbose=TRUE)
#{
#    scipen <- getOption("scipen")
#    options(scipen=100)
#    if (is.null(design)) {
#        if (verbose) message("Default design matrix\n")
#        design <- matrix(0, nrow=length(rs), ncol=length(rs), dimnames=list(NULL, paste(getNames(rs), ".wig.gz", sep="")))
#        for (i in 1:length(rs)) design[i,i] <- 1
#    }
#
#    w <- which( rowSums(design != 0) > 0 )
#    rs <- extract(rs, w, verbose=verbose)
#    probePositions <- getProbePositionsDf( getCdf(rs), verbose=verbose )
#    dmP <- extractMatrix(rs, cells=probePositions$index, verbose=verbose)
#    if(log2.adj == TRUE) diffs <- log2(dmP) %*% design[w,] else diffs <- dmP %*% design[w,]
#	
#    for (i in 1:ncol(design)) {
#        filename <- colnames(design)[i]
#        if (verbose) message("Processing column",i,"of design matrix -",filename,"\n")
#        f1 <- if (grepl("gz$",filename)) gzfile(filename, open="wt") else file(filename, open="wt")
#        for (chr in unique(probePositions$chr)) {
#            if (verbose) message(chr," ")
#            thisChr <- which(probePositions$chr==chr)
#            #Write header for this chromosome
#            writeLines(paste("variableStep chrom=", chr," span=1",sep=""), f1)
#            temp <- paste(probePositions$position[thisChr], diffs[thisChr,i], sep="\t")
#            writeLines(temp, f1)
#        }
#        if (verbose) message("\n")
#        close(f1)
#    }
#    options(scipen=scipen)
#})