예제 #1
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def toSequence(chunk, fasta):
    """convert a list of gff attributes to a single sequence.

    This function ensures correct in-order concatenation on
    positive/negative strand. Overlapping regions are merged.
    """
    if len(chunk) == 0:
        return ""

    contig, strand = chunk[0].contig, chunk[0].strand

    for gff in chunk:
        assert gff.strand == strand, "features on different strands."
        assert gff.contig == contig, "features on different contigs."

    intervals = Intervals.combine([(x.start, x.end) for x in chunk])
    lcontig = fasta.getLength(contig)
    positive = Genomics.IsPositiveStrand(strand)

    if not positive:
        intervals = [(lcontig - end, lcontig - start)
                     for start, end in intervals]
        intervals.reverse()

    s = [
        fasta.getSequence(contig, strand, start, end)
        for start, end in intervals
    ]

    return "".join(s)
예제 #2
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def combineMergedIntervals(bedfiles):
    '''combine intervals in a collection of bed files.

    Overlapping intervals between tracks are merged.

    Algorithm:

    1. collect all intervals in all tracks into a single track
    2. merge overlapping intervals
    3. report all intervals that overlap with an interval in each track.

    '''

    # get all intervals
    data_per_contig = collections.defaultdict(list)

    for bedfile in bedfiles:
        for contig in bedfile.contigs:
            i = []
            for bed in bedfile.fetch(contig, parser=pysam.asBed()):
                i.append((bed.start, bed.end))
            data_per_contig[contig].extend(i)

    # merge intervals
    for contig in list(data_per_contig.keys()):
        data_per_contig[contig] = Intervals.combine(data_per_contig[contig])

    # filter intervals - take only those present in all bedfiles
    for contig, data in sorted(data_per_contig.items()):
        for start, end in data:
            if isContainedInAll(contig, start, end, bedfiles):
                yield contig, start, end
예제 #3
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def iterator_min_feature_length(gff_iterator, min_length, feature="exon"):
    """select only those genes with a minimum length of a given feature."""
    for gffs in gff_iterator:
        intervals = [(x.start, x.end) for x in gffs if x.feature == feature]
        intervals = Intervals.combine(intervals)
        t = sum((x[1] - x[0] for x in intervals))
        if t >= min_length:
            yield gffs
예제 #4
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def annotateExons(iterator, fasta, options):
    """annotate exons within iterator."""

    gene_iterator = GTF.gene_iterator(iterator)

    ninput, noutput, noverlapping = 0, 0, 0

    for this in gene_iterator:
        ninput += 1
        intervals = collections.defaultdict(list)
        ntranscripts = len(this)

        is_negative_strand = Genomics.IsNegativeStrand(this[0][0].strand)

        for exons in this:
            # make sure these are sorted correctly
            exons.sort(key=lambda x: x.start)
            if is_negative_strand:
                exons.reverse()

            nexons = len(exons)
            for i, e in enumerate(exons):
                intervals[(e.start, e.end)].append((i + 1, nexons))

        gtf = GTF.Entry()
        gtf.fromGTF(this[0][0], this[0][0].gene_id, this[0][0].gene_id)
        gtf.addAttribute("ntranscripts", ntranscripts)

        gtfs = []
        for r, pos in intervals.items():

            g = GTF.Entry().copy(gtf)
            g.start, g.end = r
            g.addAttribute("nused", len(pos))
            g.addAttribute("pos", ",".join(["%i:%i" % x for x in pos]))
            gtfs.append(g)

        gtfs.sort(key=lambda x: x.start)

        for g in gtfs:
            options.stdout.write("%s\n" % str(g))

        # check for exon overlap
        intervals = [(g.start, g.end) for g in gtfs]
        nbefore = len(intervals)
        nafter = len(Intervals.combine(intervals))
        if nafter != nbefore:
            noverlapping += 1

        noutput += 1

    if options.loglevel >= 1:
        options.stdlog.write("# ninput=%i, noutput=%i, noverlapping=%i\n" %
                             (ninput, noutput, noverlapping))
예제 #5
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def annotateTTS(iterator, fasta, options):
    """annotate termination sites within iterator.

    Entries specified with ``--restrict-source are annotated``.
    """

    gene_iterator = GTF.gene_iterator(iterator)

    ngenes, ntranscripts, npromotors = 0, 0, 0

    for gene in gene_iterator:
        ngenes += 1
        is_negative_strand = Genomics.IsNegativeStrand(gene[0][0].strand)
        lcontig = fasta.getLength(gene[0][0].contig)
        tts = []
        transcript_ids = []
        for transcript in gene:

            ntranscripts += 1
            mi, ma = min([x.start for x in transcript
                          ]), max([x.end for x in transcript])
            transcript_ids.append(transcript[0].transcript_id)
            # if tts is directly at start/end of contig, the tss will
            # be within an exon.  otherwise, it is outside an exon.
            if is_negative_strand:
                tts.append(
                    (max(0, mi - options.promotor), max(options.promotor, mi)))
            else:
                tts.append((min(ma, lcontig - options.promotor),
                            min(lcontig, ma + options.promotor)))

        if options.merge_promotors:
            # merge the promotors (and rename - as sort order might have
            # changed)
            tts = Intervals.combine(tts)
            transcript_ids = ["%i" % (x + 1) for x in range(len(tts))]

        gtf = GTF.Entry()
        gtf.fromGTF(gene[0][0], gene[0][0].gene_id, gene[0][0].gene_id)
        gtf.source = "tts"

        x = 0
        for start, end in tts:
            gtf.start, gtf.end = start, end
            gtf.transcript_id = transcript_ids[x]
            options.stdout.write("%s\n" % str(gtf))
            npromotors += 1
            x += 1

    if options.loglevel >= 1:
        options.stdlog.write("# ngenes=%i, ntranscripts=%i, ntss=%i\n" %
                             (ngenes, ntranscripts, npromotors))
예제 #6
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def asRanges(gffs, feature=None):
    """return ranges within a set of gffs.

    Overlapping intervals are merged.

    The returned intervals are sorted.
    """

    if isinstance(feature, str):
        gg = [x for x in gffs if x.feature == feature]
    elif feature:
        gg = [x for x in gffs if x.feature in feature]
    else:
        gg = gffs[:]

    r = [(g.start, g.end) for g in gg]
    return Intervals.combine(r)
예제 #7
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def toIntronIntervals(chunk):
    '''convert a set of gtf elements within a transcript to intron coordinates.

    Will use first transcript_id found.

    Note that coordinates will still be forward strand coordinates
    '''
    if len(chunk) == 0:
        return []
    contig, strand, transcript_id = (chunk[0].contig, chunk[0].strand,
                                     chunk[0].transcript_id)
    for gff in chunk:
        assert gff.strand == strand, "features on different strands."
        assert gff.contig == contig, "features on different contigs."

    intervals = Intervals.combine([(x.start, x.end) for x in chunk
                                   if x.feature == "exon"])
    return Intervals.complement(intervals)
예제 #8
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def annotateRegulons(iterator, fasta, tss, options):
    """annotate regulons within iterator.

    Entries specied with ``--restrict-source`` are annotated.
    """

    gene_iterator = GTF.gene_iterator(iterator)

    ngenes, ntranscripts, nregulons = 0, 0, 0

    upstream, downstream = options.upstream, options.downstream

    for gene in gene_iterator:
        ngenes += 1
        is_negative_strand = Genomics.IsNegativeStrand(gene[0][0].strand)
        lcontig = fasta.getLength(gene[0][0].contig)
        regulons = []
        transcript_ids = []
        for transcript in gene:

            ntranscripts += 1
            mi, ma = min([x.start for x in transcript
                          ]), max([x.end for x in transcript])
            if tss:
                # add range to both sides of tss
                if is_negative_strand:
                    interval = ma - options.downstream, ma + options.upstream
                else:
                    interval = mi - options.upstream, mi + options.downstream
            else:
                # add range to both sides of tts
                if is_negative_strand:
                    interval = mi - options.downstream, mi + options.upstream
                else:
                    interval = ma - options.upstream, ma + options.downstream

            interval = (min(lcontig, max(0, interval[0])),
                        min(lcontig, max(0, interval[1])))

            regulons.append(interval)
            transcript_ids.append(transcript[0].transcript_id)

        if options.merge_promotors:
            # merge the regulons (and rename - as sort order might have
            # changed)
            regulons = Intervals.combine(regulons)
            transcript_ids = ["%i" % (x + 1) for x in range(len(regulons))]

        gtf = GTF.Entry()
        gtf.fromGTF(gene[0][0], gene[0][0].gene_id, gene[0][0].gene_id)
        gtf.source = "regulon"

        x = 0
        for start, end in regulons:
            gtf.start, gtf.end = start, end
            gtf.transcript_id = transcript_ids[x]
            options.stdout.write("%s\n" % str(gtf))
            nregulons += 1
            x += 1

    E.info("ngenes=%i, ntranscripts=%i, nregulons=%i" %
           (ngenes, ntranscripts, nregulons))
예제 #9
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def main(argv=None):
    """script main.

    parses command line options in sys.argv, unless *argv* is given.
    """

    if argv is None:
        argv = sys.argv

    parser = E.OptionParser(
        version="%prog version: $Id: gff2psl.py 2781 2009-09-10 11:33:14Z andreas $", usage=globals()["__doc__"])

    parser.add_option("--is-gtf", dest="is_gtf", action="store_true",
                      help="input is gtf.")

    parser.add_option("--no-header", dest="with_header", action="store_false",
                      help="do not output BLAT header [default=%default].")

    parser.add_option("-g", "--genome-file", dest="genome_file", type="string",
                      help="filename with genome.")

    parser.add_option("--queries-tsv-file", dest="input_filename_queries", type="string",
                      help="fasta filename with queries [default=%default].")

    parser.add_option("--allow-duplicates", dest="allow_duplicates", action="store_true",
                      help="""permit duplicate entries. Adjacent exons of a transcript will still be merged [default=%default]."""  )

    parser.set_defaults(is_gtf=False,
                        genome_file=None,
                        with_header=True,
                        allow_duplicates=False,
                        test=None)

    (options, args) = E.start(parser, add_pipe_options=True)

    if options.genome_file:
        genome_fasta = IndexedFasta.IndexedFasta(options.genome_file)
    else:
        genome_fasta = None

    if options.input_filename_queries:
        queries_fasta = IndexedFasta.IndexedFasta(
            options.input_filename_queries)
    else:
        queries_fasta = None

    ninput, noutput, nskipped = 0, 0, 0

    if options.is_gtf:
        iterator = GTF.transcript_iterator(GTF.iterator_filtered(GTF.iterator(sys.stdin),
                                                                 feature="exon"),
                                           strict=not options.allow_duplicates)
    else:
        iterator = GTF.joined_iterator(GTF.iterator(sys.stdin))

    if options.with_header:
        options.stdout.write(Blat.Match().getHeader() + "\n")

    for gffs in iterator:

        if options.test and ninput >= options.test:
            break

        ninput += 1

        result = alignlib_lite.py_makeAlignmentBlocks()

        xstart = 0

        intervals = Intervals.combine([(gff.start, gff.end) for gff in gffs])

        for start, end in intervals:
            xend = xstart + end - start

            result.addDiagonal(xstart, xend,
                               start - xstart)
            xstart = xend

        entry = Blat.Match()
        entry.mQueryId = gffs[0].transcript_id
        entry.mSbjctId = gffs[0].contig
        entry.strand = gffs[0].strand

        if genome_fasta:
            if entry.mSbjctId in genome_fasta:
                entry.mSbjctLength = genome_fasta.getLength(entry.mSbjctId)
            else:
                entry.mSbjctLength = result.getColTo()

        if queries_fasta:
            if entry.mQueryId in queries_fasta:
                entry.mQueryLength = queries_fasta.getLength(entry.mQueryId)
        else:
            entry.mQueryLength = result.getRowTo()

        entry.fromMap(result)

        options.stdout.write(str(entry) + "\n")
        noutput += 1

    E.info("ninput=%i, noutput=%i, nskipped=%i" % (ninput, noutput, nskipped))

    E.stop()