def demo():
    """
    A demonstration showing how each tree transform can be used.
    """  
      
    from en.parser.nltk_lite.draw.tree import draw_trees
    from en.parser.nltk_lite.parse import bracket_parse
    from en.parser.nltk_lite.parse import treetransforms
    from copy import deepcopy
    
    # original tree from WSJ bracketed text
    sentence = "(TOP (S (S (VP (VBN Turned) (ADVP (RB loose)) (PP (IN in) (NP (NP (NNP Shane) (NNP Longman) (POS 's)) (NN trading) (NN room))))) (, ,) (NP (DT the) (NN yuppie) (NNS dealers)) (VP (AUX do) (NP (NP (RB little)) (ADJP (RB right)))) (. .)))"
    tree = bracket_parse(sentence)
    
    # collapse subtrees with only one child
    collapsedTree = deepcopy(tree)
    treetransforms.collapseUnary(collapsedTree)
    
    # convert the tree to CNF
    cnfTree = deepcopy(collapsedTree)
    treetransforms.chomskyNormalForm(cnfTree)
    
    # convert the tree to CNF with parent annotation (one level) and horizontal smoothing of order two
    parentTree = deepcopy(collapsedTree)
    treetransforms.chomskyNormalForm(parentTree, horzMarkov=2, vertMarkov=1)
    
    # convert the tree back to its original form (used to make CYK results comparable)
    original = deepcopy(parentTree)
    treetransforms.unChomskyNormalForm(original)
    
    # convert tree back to bracketed text
    sentence2 = treetransforms.toTreebank(original)
    print "Sentences the same? ", sentence == sentence2
    
    draw_trees(tree, collapsedTree, cnfTree, parentTree, original)
Example #2
0
def main():
    import sys
    from optparse import OptionParser, OptionGroup
    usage = """%%prog [options] [grammar_file]""" % globals()

    opts = OptionParser(usage=usage)
    opts.add_option("-c",
                    "--components",
                    action="store_true",
                    dest="show_components",
                    default=0,
                    help="show hole semantics components")
    opts.add_option("-r",
                    "--raw",
                    action="store_true",
                    dest="show_raw",
                    default=0,
                    help="show the raw hole semantics expression")
    opts.add_option("-d",
                    "--drawtrees",
                    action="store_true",
                    dest="draw_trees",
                    default=0,
                    help="show formula trees in a GUI window")
    opts.add_option("-v",
                    "--verbose",
                    action="count",
                    dest="verbosity",
                    default=0,
                    help="show more information during parse")

    (options, args) = opts.parse_args()

    if len(args) > 0:
        filename = args[0]
    else:
        filename = 'hole.cfg'

    print 'Reading grammar file', filename
    grammar = GrammarFile.read_file(filename)
    parser = grammar.earley_parser(trace=options.verbosity)

    # Prompt the user for a sentence.
    print 'Sentence: ',
    line = sys.stdin.readline()[:-1]

    # Parse the sentence.
    tokens = list(tokenize.whitespace(line))
    trees = parser.get_parse_list(tokens)
    print 'Got %d different parses' % len(trees)

    for tree in trees:
        # Get the semantic feature from the top of the parse tree.
        sem = tree[0].node['sem'].simplify()

        # Skolemise away all quantifiers.  All variables become unique.
        sem = sem.skolemise()

        # Reparse the semantic representation from its bracketed string format.
        # I find this uniform structure easier to handle.  It also makes the
        # code mostly independent of the lambda calculus classes.
        usr = bracket_parse(str(sem))

        # Break the hole semantics representation down into its components
        # i.e. holes, labels, formula fragments and constraints.
        hole_sem = HoleSemantics(usr)

        # Maybe print the raw semantic representation.
        if options.show_raw:
            print
            print 'Raw expression'
            print usr

        # Maybe show the details of the semantic representation.
        if options.show_components:
            print
            print 'Holes:       ', hole_sem.holes
            print 'Labels:      ', hole_sem.labels
            print 'Constraints: ', hole_sem.constraints
            print 'Top hole:    ', hole_sem.top_hole
            print 'Top labels:  ', hole_sem.top_most_labels
            print 'Fragments:'
            for (l, f) in hole_sem.fragments.items():
                print '\t%s: %s' % (l, f)

        # Find all the possible ways to plug the formulas together.
        pluggings = hole_sem.pluggings()

        # Build FOL formula trees using the pluggings.
        trees = map(hole_sem.formula_tree, pluggings)

        # Print out the formulas in a textual format.
        n = 1
        for tree in trees:
            print
            print '%d. %s' % (n, tree)
            n += 1

        # Maybe draw the formulas as trees.
        if options.draw_trees:
            draw_trees(*trees)

        print
        print 'Done.'
Example #3
0
def main():
    import sys
    from optparse import OptionParser, OptionGroup
    usage = """%%prog [options] [grammar_file]""" % globals()

    opts = OptionParser(usage=usage)
    opts.add_option("-c", "--components",
	action="store_true", dest="show_components", default=0,
	help="show hole semantics components")
    opts.add_option("-r", "--raw",
	action="store_true", dest="show_raw", default=0,
	help="show the raw hole semantics expression")
    opts.add_option("-d", "--drawtrees",
	action="store_true", dest="draw_trees", default=0,
	help="show formula trees in a GUI window")
    opts.add_option("-v", "--verbose",
	action="count", dest="verbosity", default=0,
	help="show more information during parse")

    (options, args) = opts.parse_args()

    if len(args) > 0:
        filename = args[0]
    else:
        filename = 'hole.cfg'

    print 'Reading grammar file', filename
    grammar = GrammarFile.read_file(filename)
    parser = grammar.earley_parser(trace=options.verbosity)

    # Prompt the user for a sentence.
    print 'Sentence: ',
    line = sys.stdin.readline()[:-1]

    # Parse the sentence.
    tokens = list(tokenize.whitespace(line))
    trees = parser.get_parse_list(tokens)
    print 'Got %d different parses' % len(trees)

    for tree in trees:
        # Get the semantic feature from the top of the parse tree.
        sem = tree[0].node['sem'].simplify()

        # Skolemise away all quantifiers.  All variables become unique.
        sem = sem.skolemise()

        # Reparse the semantic representation from its bracketed string format.
        # I find this uniform structure easier to handle.  It also makes the
        # code mostly independent of the lambda calculus classes.
        usr = bracket_parse(str(sem))

        # Break the hole semantics representation down into its components
        # i.e. holes, labels, formula fragments and constraints.
        hole_sem = HoleSemantics(usr)

        # Maybe print the raw semantic representation.
        if options.show_raw:
            print
            print 'Raw expression'
            print usr

        # Maybe show the details of the semantic representation.
        if options.show_components:
            print
            print 'Holes:       ', hole_sem.holes
            print 'Labels:      ', hole_sem.labels
            print 'Constraints: ', hole_sem.constraints
            print 'Top hole:    ', hole_sem.top_hole
            print 'Top labels:  ', hole_sem.top_most_labels
            print 'Fragments:'
            for (l,f) in hole_sem.fragments.items():
                print '\t%s: %s' % (l, f)

        # Find all the possible ways to plug the formulas together.
        pluggings = hole_sem.pluggings()

        # Build FOL formula trees using the pluggings.
        trees = map(hole_sem.formula_tree, pluggings)

        # Print out the formulas in a textual format.
        n = 1
        for tree in trees:
            print
            print '%d. %s' % (n, tree)
            n += 1

        # Maybe draw the formulas as trees.
        if options.draw_trees:
            draw_trees(*trees)

        print
        print 'Done.'