parser.py

import warnings
from corpus import idgcorpus, itreecorpus, isdgcorpus

from treebank import TreeUtil


def rhead(dg):
    l = dg.length()

    parsed = dg.copy()
    for n in parsed.nodeiter():
        if n._id < l:
            n.setHead(n._id + 1)
        else:
            n.setHead(0)

    return parsed


def lhead(dg):
    l = dg.length()

    parsed = dg.copy()
    for n in parsed.nodeiter():
        if n._id > 1:
            n.setHead(n._id - 1)
        else:
            n.setHead(0)

    return parsed


def lbranch(t, _root=True, _unary=True):
    n = len(t.leaves())
    return set((0, l) for l in range(1 if _unary else 2, n + 1 if _root else n))


def rbranch(t, _root=True, _unary=True):
    n = len(t.leaves())
    return set((l, n) for l in range(n - 1 if _unary else n - 2, -1 if _root else 0, -1))


def gbranch(t, _root=True, _unary=True):
    return TreeUtil.bracketing(t, root=_root, unary=_unary)


def toString(_set):
    return ",".join("(%s,%s)" % (lb, rb) for lb, rb in _set)


def parse_and_store(finput, foutput, model=rhead):
    with open(foutput, "w") as fp:
        if model in (rhead, lhead):
            fp.write("\n\n".join(str(model(dg)) for dg in idgcorpus(finput)))
        else:
            fp.write("\n".join(
                "%d:%s" % ( len(t.leaves()), toString(model(t, _root=True, _unary=False))) for t in itreecorpus(
                    finput)))


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser(description='Some popular baseline parsings for given corpus files')
    parser.add_argument('finput', type=str,
                        help='Source corpus file(s) to be parsed')
    parser.add_argument('foutput', type=str,
                        help='Target file including parsing')
    group = parser.add_mutually_exclusive_group()
    group.add_argument('--rhead', action='store_true', help="Right head parsing")
    group.add_argument('--lhead', action='store_true', help="Left head parsing")
    group.add_argument('--gbranch', action='store_true', help="Gold bracketing")
    group.add_argument('--rbranch', action='store_true', help="Right bracketing")
    group.add_argument('--lbranch', action='store_true', help="Left bracketing")
    args = parser.parse_args()

    if args.rhead:
        if not isdgcorpus(args.finput):
            warnings.warn("Corpus seems to be a tree corpus. Failover to Left Branch parsing")
            parse_and_store(args.finput, args.foutput, lbranch)
        else:
            parse_and_store(args.finput, args.foutput, rhead)
    elif args.lhead:
        if not isdgcorpus(args.finput):
            warnings.warn("Corpus seems to be a tree corpus. Failover to Right Branch parsing")
            parse_and_store(args.finput, args.foutput, rbranch)
        else:
            parse_and_store(args.finput, args.foutput, lhead)
    elif args.rbranch:
        if isdgcorpus(args.finput):
            warnings.warn("Corpus seems to be a dependency corpus. Failover to Left Head parsing")
            parse_and_store(args.finput, args.foutput, lhead)
        else:
            parse_and_store(args.finput, args.foutput, rbranch)
    elif args.lbranch:
        if isdgcorpus(args.finput):
            warnings.warn("Corpus seems to be a dependency corpus. Failover to Right Head parsing")
            parse_and_store(args.finput, args.foutput, rhead)
        else:
            parse_and_store(args.finput, args.foutput, lbranch)
    else:
        if isdgcorpus(args.finput):
            warnings.warn("Corpus seems to be a dependency corpus. Gold parsing is only valid for tree corpus.")
        else:
            parse_and_store(args.finput, args.foutput, gbranch)