def pcfg(train_idx=None, smoothing=None):
"""
productions = []
item = treebank._fileids[0]
print("ITEM\n\n",item,"\n\n")
for tree in treebank.parsed_sents(item)[:3]:
# perform optional tree transformations, e.g.:
tree.collapse_unary(collapsePOS = False)
tree.chomsky_normal_form(horzMarkov = 2)
productions += tree.productions()
"""
if train_idx == None:
train_idx = (len(treebank.fileids()) * 3) // 4
productions = []
for item in treebank.fileids()[0:train_idx]:
for tree in treebank.parsed_sents(item):
tree.collapse_unary(
collapsePOS=False) # Remove unary production rule
tree.chomsky_normal_form(
horzMarkov=2
) # Convert into chomsky normal form i.e., A->(B,C,D) into A->(B,E) E->(C,D)
productions += tree.productions()
S = Nonterminal('S')
if smoothing == None:
grammar = learn_pcfg(S, productions)
elif smoothing == 'L1':
grammar = smoothing_pcfg(S, productions)
with open('grammar.pkl', 'wb') as f:
pickle.dump(grammar, f)
return grammar
def main():
# print(nltk.corpus.treebank.parsed_sents('wsj_0001.mrg')[0])
# nltk.corpus.treebank.parsed_sents('wsj_0001.mrg')[0].draw()
# print("Induce PCFG grammar from treebank data:")
#
productions = []
print(len(treebank.fileids()))
for item in treebank.fileids(): # Goes through all trees
for tree in treebank.parsed_sents(item):
# perform optional tree transformations, e.g.:
tree.collapse_unary(collapsePOS = False)# Remove branches A-B-C into A-B+C
tree.chomsky_normal_form(horzMarkov = 2)# Remove A->(B,C,D) into A->B,C+D->D
productions += tree.productions()
# #
# # print(type(productions[0]))
# #
S = Nonterminal('S')
grammar = induce_pcfg(S, productions)
# # # print(grammar) # This is a PCFG
# pickle.dump(grammar, open("tbank-grammar.p", "wb"))
# t = time.time()
# grammar = pickle.load(open("tbank-grammar.p", "rb"))
# textf = open("lexicon.txt", "w")
# n = textf.write(str(reduce(lambda a, b: a + "\n" + b, list(filter(lambda x: "'" in x, str(grammar).split("\n"))))))
# textf.close()
# print(time.time()-t)
parser = ViterbiParser(grammar)
# pickle.dump(parser, open("cky-parser.p", "wb"))
# parser = pickle.load(open("cky-parser.p", "rb"))
parser.trace(0)
sent = "John will join the board"
tokens = sent.split()
try:
grammar.check_coverage(tokens)
print("All words covered")
parses = parser.parse_all(tokens)
if parses:
lp = len(parses)
print(lp)
print(parses[0].label())
# parses[0].draw()
p = reduce(lambda a,b:a+b.prob(), list(filter(lambda x: x.label() == 'S', parses)), 0.0)
else:
p = 0
print("Probability:", p)
except:
print("Some words not covered")
def sentences():
for f in treebank.fileids():
for t in treebank.parsed_sents(f):
t.chomsky_normal_form(horzMarkov=1)
t.collapse_unary(collapsePOS=True)
yield (t, t.leaves())
def demo():
"""
A demonstration of the porter stemmer on a sample from
the Penn Treebank corpus.
"""
from nltk.corpus import treebank
from nltk import stem
stemmer = stem.PorterStemmer()
orig = []
stemmed = []
for item in treebank.fileids()[:3]:
for (word, tag) in treebank.tagged_words(item):
orig.append(word)
stemmed.append(stemmer.stem(word))
# Convert the results to a string, and word-wrap them.
results = ' '.join(stemmed)
results = re.sub(r"(.{,70})\s", r'\1\n', results + ' ').rstrip()
# Convert the original to a string, and word wrap it.
original = ' '.join(orig)
original = re.sub(r"(.{,70})\s", r'\1\n', original + ' ').rstrip()
# Print the results.
print('-Original-'.center(70).replace(' ', '*').replace('-', ' '))
print(original)
print('-Results-'.center(70).replace(' ', '*').replace('-', ' '))
print(results)
print('*' * 70)
def demo():
"""
A demonstration of the porter stemmer on a sample from
the Penn Treebank corpus.
"""
from nltk import stem
from nltk.corpus import treebank
stemmer = stem.PorterStemmer()
orig = []
stemmed = []
for item in treebank.fileids()[:3]:
for (word, tag) in treebank.tagged_words(item):
orig.append(word)
stemmed.append(stemmer.stem(word))
# Convert the results to a string, and word-wrap them.
results = " ".join(stemmed)
results = re.sub(r"(.{,70})\s", r"\1\n", results + " ").rstrip()
# Convert the original to a string, and word wrap it.
original = " ".join(orig)
original = re.sub(r"(.{,70})\s", r"\1\n", original + " ").rstrip()
# Print the results.
print("-Original-".center(70).replace(" ", "*").replace("-", " "))
print(original)
print("-Results-".center(70).replace(" ", "*").replace("-", " "))
print(results)
print("*" * 70)
def test_GrammarParser():
import nltk
from nltk.corpus import treebank
grammar = r"""NP:
{<DT>*(<NN>|<NNP>|<NNS>)+} # Chunk everything
}<VBD|IN>+{ # Chink sequences of VBD and IN
"""
# tree=treebank.parsed_sents('wsj_0001.mrg')[0]
# print tree
grammar_VP = r"""VP:
{<VBZ><VP>}
"""
# tree=nltk.RegexpParser(grammar).parse(treebank.parsed_sents('wsj_0001.mrg')[0].pos())
# print tree
fileids = treebank.fileids()
# for fileld in fileids:
for i in range(len(fileids)):
if i > 10:
break
# trees=treebank.parsed_sents(fileld)
trees = treebank.parsed_sents(fileids[i])
for tree in trees:
tree_Gram = nltk.RegexpParser(grammar).parse(tree)
for subtree in tree_Gram.subtrees():
if subtree.label() == "VP":
print subtree
def gen_corpus(path, threshold):
"""
src: http://www.nltk.org/_modules/nltk/tree.html
corpora from wsj_0001.mrg to wsj_0199.mrg
e.g.: t = treebank.parsed_sents('wsj_0001.mrg')[0]
to visualize a tree: t.draw()
:param path: save to path
:param threshold: minimum length of a sentence to keep
:return: none
"""
boundaries = []
sentences = []
for t in treebank.parsed_sents(treebank.fileids()):
flat = _flatten_tree(t, threshold)
if flat:
boundaries.append(flat)
sentence = ' '.join(t.leaves()).translate(PUNC_TRANS).lower()
sentence = re.sub(r' +', ' ', sentence)
# replace digit(s) as 'x'(s)
sentences.append(re.sub(r'\d', 'x', sentence).strip())
_check_length_match(boundaries, sentences)
with open(path + "/boundaries.txt", 'w') as f:
f.write('1'.join(boundaries))
with open(path + "/sentences.txt", 'w') as f:
f.write(' '.join(sentences))
def trial_run_with_treebank():
files = treebank.fileids()
files = files[:100] # make shorter for setup
gram = makeGrammarFromTreebank(files)
myparser = cky_parser.ckyparser(gram,Nonterminal('S'))
chart,mytrees = myparser.probabilistic_parse_from_sent("I saw John with my telescope")
print(mytrees)
def load_data(self, percentage):
print("Started Loading the Data")
# Get the complete data
data_set = treebank.fileids()
# Partition the data into train and test data sets
training_data_fileIds = [file for file in data_set if "wsj_00" in str(file)]
testing_data_fileIds = [file for file in data_set if "wsj_01" in str(file)]
# How much percentage of files consider for training?
index = int(percentage*len(training_data_fileIds))
training_data_fileIds = training_data_fileIds[:index]
tagged_training_data = treebank.tagged_sents(fileids=training_data_fileIds)
tagged_testing_data = treebank.tagged_sents(fileids=testing_data_fileIds)
tagged_training_words = treebank.tagged_words(fileids=training_data_fileIds)
tagged_testing_words = treebank.tagged_words(fileids=testing_data_fileIds)
# print(len(tagged_training_data1), len(tagged_testing_data1))
# UnTag the data for other uses
untagged_training_data = [untag(item) for item in tagged_training_data]
untagged_testing_data = [untag(item) for item in tagged_testing_data]
print("Data Loaded Successfully. Stats are")
print("Training Data Sentences: ", len(tagged_training_data))
print("Testing Data Sentences: ", len(tagged_testing_data))
return tagged_training_data, tagged_testing_data, tagged_training_words, tagged_testing_words, untagged_training_data, untagged_testing_data
def sentences():
for f in treebank.fileids():
for t in treebank.parsed_sents(f):
t.chomsky_normal_form(horzMarkov=1)
t.collapse_unary(collapsePOS=True)
yield (t, t.leaves())
def demo():
"""
A demonstration of the porter stemmer on a sample from
the Penn Treebank corpus.
"""
from nltk.corpus import treebank
from nltk import stem
stemmer = stem.PorterStemmer()
orig = []
stemmed = []
for item in treebank.fileids()[:3]:
for (word, tag) in treebank.tagged_words(item):
orig.append(word)
stemmed.append(stemmer.stem(word))
# Convert the results to a string, and word-wrap them.
results = ' '.join(stemmed)
results = re.sub(r"(.{,70})\s", r'\1\n', results + ' ').rstrip()
# Convert the original to a string, and word wrap it.
original = ' '.join(orig)
original = re.sub(r"(.{,70})\s", r'\1\n', original + ' ').rstrip()
# Print the results.
print('-Original-'.center(70).replace(' ', '*').replace('-', ' '))
print(original)
print('-Results-'.center(70).replace(' ', '*').replace('-', ' '))
print(results)
print('*' * 70)
def read_split_treebank():
fileids = treebank.fileids()
seed.shuffle(fileids)
split = int(len(fileids) * 0.8)
x_train = fileids[:split]
x_test = fileids[split:]
print('Train - Test: ', len(x_train), len(x_test))
return x_train, x_test
def read_treebank(input_vocab_size=10000, output_vocab_size=10000, seq_len=10):
all_sents = []
for fname in treebank.fileids():
sents = treebank.sents(fname)
if sents:
all_sents.extend(sents)
return read_dataset(all_sents, input_vocab_size, output_vocab_size,
seq_len)
def _induce_grammar(self):
self.productions = []
for tree in treebank.parsed_sents(treebank.fileids()):
# perform optional tree transformations, e.g.:
tree.collapse_unary(
collapsePOS=False) # Remove branches A-B-C into A-B+C
tree.chomsky_normal_form(
horzMarkov=2) # Remove A->(B,C,D) into A->B,C+D->D
self.productions += tree.productions()
def read_data():
treebank_tagged_sents = list(
chain(*[[tree.pos() for tree in treebank.parsed_sents(pf)] for pf in treebank.fileids()]))
words_list = [[tag[0] for tag in sent] for sent in treebank_tagged_sents]
labels = [[tag[1] for tag in sent] for sent in treebank_tagged_sents]
words = []
max_words = 0
for sent in words_list:
words.extend(sent)
max_words = max(max_words, len(sent))
print("Max. Words:", max_words)
seq_length = 100
print("Seq. Length:", seq_length)
words = list(set(words))
print("Number of Words:", len(words))
unique_labels = []
for sent in labels:
unique_labels.extend(sent)
unique_labels = list(set(unique_labels))
print("Number of Unique Labels:", len(unique_labels))
word2id = {word: i + 1 for i, word in enumerate(words)}
id2word = {i + 1: word for i, word in enumerate(words)}
X_data = []
Y_data = []
for i in range(len(treebank_tagged_sents)):
for j in range(len(words_list[i])):
_x = [0] * max_words
for k in range(j + 1):
_x[j - k] = word2id[words_list[i][k]]
_x = _x[:seq_length]
_x.reverse()
X_data.append(_x)
Y_data.append(one_hot(labels[i][j], unique_labels))
X_data = np.array(X_data, dtype=np.int32)
Y_data = np.array(Y_data, dtype=np.float32)
print(X_data.shape)
print(Y_data.shape)
return X_data, Y_data, unique_labels, words, word2id, id2word
def get_training_and_test_split(config):
files = treebank.fileids()
random.shuffle(files)
training = files[:int(0.9 * len(files))]
test = files[int(0.9 * len(files)):]
with open(config.train_set, 'w') as file:
file.write(",".join(training))
with open(config.test_set, 'w') as file:
file.write(",".join(test))
def getGrammar():
fileid = treebank.fileids()
trainfiles = fileid[:160]
#testfiles=fileid[0.8*len(fileid):]
productions = []
for item in trainfiles:
for tree in treebank.parsed_sents(item):
# perform optional tree transformations, e.g.:
tree.collapse_unary(
collapsePOS=False) # Remove branches A-B-C into A-B+C
tree.chomsky_normal_form(
horzMarkov=2) # Remove A->(B,C,D) into A->B,C+D->D
productions += tree.productions()
lhs_prod = [p.lhs() for p in productions]
rhs_prod = [p.rhs() for p in productions]
set_prod = set(productions)
list_prod = list(set_prod)
token_rule = []
for ele in list_prod:
if ele.is_lexical():
token_rule.append(ele)
set_token_rule = set(p.lhs() for p in token_rule)
list_token_rule = list(set_token_rule)
corr_list_token_rule = []
for word in list_token_rule:
if str(word).isalpha():
corr_list_token_rule.append(word)
continue
#print(corr_list_token_rule)
import nltk
a = []
for tok in corr_list_token_rule:
#lhs = nltk.grammar.Nonterminal('UNK')
lhs = 'UNK'
rhs = [u'UNK']
UNK_production = nltk.grammar.Production(lhs, rhs)
lhs2 = nltk.grammar.Nonterminal(str(tok))
a.append(nltk.grammar.Production(lhs2, [lhs]))
token_rule.extend(a)
list_prod.extend(a)
S = Nonterminal('S')
grammar = induce_pcfg(S, list_prod)
return grammar
def ptb_wsj_set():
trainsize = 3500
testsize = 300
ts = list(
itertools.chain(*(treebank.parsed_sents(fid)
for fid in treebank.fileids())))[:trainsize +
testsize]
testsents = [" ".join(s.leaves()) for s in ts[trainsize:]]
# with open("/tmp/trees.json", 'w') as f:
# lins = []
# for t in ts[:trainsize]:
# def lin(t):
# if isinstance(t, str):
# label = t
# cs = []
# else:
# label = t.label()
# cs = t
#
# if '"' in label:
# raise Exception("»\"« occuring in data! :O")
#
# return "{\"label\": \"" + label + "\", \"children\": [" + ",".join([lin(c) for c in cs]) + "]}"
# lins.append(lin(t))
# print("[", ",\n".join(lins), "]", file = f)
#
# with open("/tmp/test.txt", 'w') as f:
# for s in testsents:
# print(s, file = f)
ts = ts[:trainsize]
def parse_treebank_grammar(treat_nt):
def getrules(t):
lhs = treat_nt(t.label())
rhs = []
for x in t:
if isinstance(x, str):
rhs.append(x)
else:
rhs.append(treat_nt(x.label()))
for r in getrules(x):
yield r
yield (lhs, tuple(rhs))
return normalize_rules(itertools.chain(*(getrules(t) for t in ts)))
rules, ntdict = intify_prules(parse_treebank_grammar)
#test = ["the old man", "something was .", "something was at the stock market today .", "Pierre Vinken , 61 years old , will join the board as a nonexecutive director Nov. 29 ."]
return (rules, ntdict), testsents
def greedy_backward_selection():
extractor = funtag_features.extract_features
# funtag_features.availbale_features = []
best_f_score = 0.0
all_features = ['label','head_pos','head','yeild','alt_head','alt_pos', 'parent_labels']
# , 'grandmother_label','sister_labels','sister_poss','sister_head']
best_features = list(all_features)
td_files, test_files = train_test_split(treebank.fileids(),
train_size=0.8,
random_state=0)
train_files, dev_files = train_test_split(td_files,
train_size=0.8,
random_state=0)
while True:
f_score_feature = []
for f in all_features:
# funtag_features.availbale_features.append(f)
if f in best_features:
best_features.remove(f)
X_train, Y_train = read_treebank_files(train_files, extractor, best_features)
classifier = train_scikit_classifier(X_train, Y_train)
X_eval, Y_eval = read_treebank_files(dev_files, extractor, best_features)
Y_out = classifier.predict(X_eval)
print('Done training and evaluating with features:', best_features)
stats = {'*ALL*': PRF()}
all_tags = sorted(set(t for ts in (Y_eval + list(Y_out))
for t in to_taglist(ts)))
for tag in all_tags:
stats[tag] = PRF()
compute_statistics(Y_eval, Y_out, stats)
f_score_feature.append((stats['*ALL*'].f1(),f))
best_features.append(f)
if best_f_score < max(f_score_feature)[0] :
best_f_score = max(f_score_feature)[0]
best_features.remove(max(f_score_feature)[1])
all_features.remove(max(f_score_feature)[1])
else:
break
if len(all_features) == 0:
break
print('Done with greedy_forward_selection..... ')
print('Features are: ', best_features)
print('Overall statistics:')
print(' #corr #guess #true precision recall F-score')
print(' {0: >4} {1: >4} {2: >4} {3:0.4f} {4:0.4f} {5:0.4f}'.format(*stats['*ALL*'].all()))
print('Statistics for each function tag:')
print('tag #corr #guess #true precision recall F-score')
for label in all_tags:
print('{0} {1: >4} {2: >4} {3: >4} {4:0.4f} {5:0.4f} {6:0.4f}'.format(label, *stats[label].all()))
def get_trees_sentences():
trees = []
sentences = []
for file in treebank.fileids():
for tree in treebank.parsed_sents(file):
tree_str = str(tree)
trees.append(tree_str)
for sentence in treebank.sents(file):
s = ""
s = " ".join(words for words in sentence)
sentences.append(s)
assert len(trees) == len(sentences)
sentences = list(map(lambda x: x.lower(), sentences))
return (trees, sentences)
def test_Phrase():
import nltk
from nltk.corpus import treebank
fileids = treebank.fileids()
grammar = r"""
ADVP:{<RB>(<CC>*<RB>*|<JJ>*)}
{}
"""
for fileld in fileids:
sents = treebank.tagged_sents(fileld)
for sent in sents:
tree_Gram = nltk.RegexpParser(grammar).parse(sent)
for subtree in tree_Gram.subtrees():
if subtree.label() == "ADVP":
print subtree
def train():
files = tb.fileids()
data = list(tb.parsed_sents(files))
# 80:20 split
split = int(len(data) * 0.8)
train_data = data[:split]
test_data = data[split:]
P_grammar, P_non_terms, P_vocab, P_term_parents, P_parents_count = pcfg.pcfg(
train_data)
total_precision = 0
toal_recall = 0
total_f1_score = 0
i = 0
for test in test_data:
print('Test', i)
i += 1
try:
words = test.leaves()
scores, backs = cky_parsing(words, copy(P_grammar),
copy(P_non_terms), copy(P_vocab),
copy(P_term_parents),
copy(P_parents_count))
start = Tree(Nonterminal('S'), [])
if scores[0][len(words)][Nonterminal('S')] == 0:
start = get_start(scores, len(words))
predicted_tree = build_tree(start, 0, len(words), backs,
P_non_terms)
clean_tree(predicted_tree)
predicted_tree.un_chomsky_normal_form()
precision, recall, f1_score = evaluate(words, predicted_tree, test)
print(precision, recall, f1_score)
total_precision += precision
toal_recall += recall
total_f1_score += f1_score
except:
print('***************Failed', i - 1)
continue
total_precision /= len(test_data)
toal_recall /= len(test_data)
total_f1_score /= len(test_data)
print('Precision', total_precision)
print('Recall', toal_recall)
print('F1_score', total_f1_score)
def getProductions(pos):
from nltk.corpus import treebank
fileids = treebank.fileids()
pos_ProductionList = []
for fileld in fileids:
trees = treebank.parsed_sents(fileld)
for tree in trees:
productions = tree.productions()
for production in productions:
if str(production.lhs()) == pos:
pos_ProductionList.append(production)
c_POS = Counter(pos_ProductionList)
c_POS_sorted = sorted(c_POS.iteritems(),
key=lambda asd: asd[1],
reverse=True)
print c_POS_sorted
def PCFG_Section():
toy_pcfg1 = PCFG.fromstring("""
S -> NP VP [1.0]
NP -> Det N [0.5] | NP PP [0.25] | 'John' [0.1] | 'I' [0.15]
Det -> 'the' [0.8] | 'my' [0.2]
N -> 'man' [0.5] | 'telescope' [0.5]
VP -> VP PP [0.1] | V NP [0.7] | V [0.2]
V -> 'ate' [0.35] | 'saw' [0.65]
PP -> P NP [1.0]
P -> 'with' [0.61] | 'under' [0.39]
""")
pcfg_prods = toy_pcfg1.productions()
pcfg_prod = pcfg_prods[2]
print('A PCFG production:', pcfg_prod)
print('pcfg_prod.lhs() =>', pcfg_prod.lhs())
print('pcfg_prod.rhs() =>', pcfg_prod.rhs())
print('pcfg_prod.prob() =>', pcfg_prod.prob())
# extract productions from three trees and induce the PCFG
print("Induce PCFG grammar from treebank data:")
productions = []
for item in treebank.fileids()[:2]:
for tree in treebank.parsed_sents(item):
# print(" ".join(tree.leaves()))
# perform optional tree transformations, e.g.:
# tree.collapse_unary(collapsePOS = False)# Remove branches A-B-C into A-B+C
# tree.chomsky_normal_form(horzMarkov = 2)# Remove A->(B,C,D) into A->B,C+D->D
prods = tree.productions()
# print(prods[0].prob())
productions += prods
S = Nonterminal('S')
grammar = induce_pcfg(S, productions)
# print(grammar) # This is a PCFG
### Parsing section below ###
print("\nParse sentence using induced grammar:")
parser = pchart.InsideChartParser(grammar)
parser.trace(1)
sent = treebank.parsed_sents('wsj_0001.mrg')[0]
print(sent.prob())
def test_VBPenn():
from nltk.corpus import treebank
fileids = treebank.fileids()
VBContexts = []
for i in range(len(fileids)):
sentPOSList = treebank.tagged_sents(fileids[i])
for sentPOS in sentPOSList:
# print 'sentPOS',sentPOS
VBContext = getVBContext(sentPOS)
# print 'VBContext',VBContext
if len(VBContext) != 0:
POSList = ''
for wordPOS in VBContext:
# print 'wordPOS',wordPOS
POSList += wordPOS[1] + '+'
VBContexts.append((POSList, VBContext))
print VBContexts
def get_words():
"""
Returns list of words from nltk treebank
"""
import nltk
nltk.download("treebank")
from nltk.corpus import treebank
word_ls = []
for item in treebank.fileids():
for (word, tag) in treebank.tagged_words(item):
# assuming the words are allready lowered
word = word.lower()
word_ls.append(word)
word_ls = list(set(word_ls))
return word_ls
def get_trees(fileids=None, verbose=False):
"""
Get the CNF trees for the treebank fileids given, or for the entire treebank
"""
if not fileids:
# Get the Penn Treebank corpus
fileids = treebank.fileids()
# Get the sentence-trees in each file
tree_lists = [treebank.parsed_sents(file_id) for file_id in fileids]
trees = [sent for sent_list in tree_lists for sent in sent_list]
if verbose:
print("obtained", len(trees), "trees from the corpus.")
cnf_trees = [ctc.convert_tree(t) for t in trees]
if verbose:
print("converted", len(trees), "trees to cnf.")
return cnf_trees
def make_PCFG_grammar():
'''
Forms a PCFG grammar utilizing the first 1963 files
in the WSJ treebank
'''
# Save a list of all produced PCFG rules given the tested data
PCFG_rules = []
for item in treebank.fileids()[:1964]:
# We want to first get rid of all non-binary branchings of the tree
for tree in treebank.parsed_sents(item):
tree.collapse_unary(collapsePOS = False)
tree.chomsky_normal_form(horzMarkov = 2)
PCFG_rules += tree.productions()
# Induce the PCFG grammar
S = Nonterminal('S')
PCFG_grammar = induce_pcfg(S, PCFG_rules)
return PCFG_grammar
def parse(sent):
files = tb.fileids()
data = list(tb.parsed_sents(files))
P_grammar, P_non_terms, P_vocab, P_term_parents, P_parents_count = pcfg.pcfg(
data)
words = casual_tokenize(str(sent))
scores, backs = cky_parsing(words, copy(P_grammar), copy(P_non_terms),
copy(P_vocab), copy(P_term_parents),
copy(P_parents_count))
start = Tree(Nonterminal('S'), [])
if scores[0][len(words)][Nonterminal('S')] == 0:
start = get_start(scores, len(words))
predicted_tree = build_tree(start, 0, len(words), backs, P_non_terms)
clean_tree(predicted_tree)
predicted_tree.un_chomsky_normal_form()
print('Parsed Tree')
print(predicted_tree)
def buildpcfg(): # call this function once then pickle the PCFG
productions = []
for item in treebank.fileids():
for tree in treebank.parsed_sents(item):
# perform optional tree transformations, e.g.:
tree.collapse_unary(collapsePOS=False) # Remove branches A-B-C into A-B+C
tree.chomsky_normal_form(horzMarkov=2) # Remove A->(B,C,D) into A->B,C+D->D
productions += tree.productions()
''' this just overwrites everything to 'X' apparently
for production in productions: #rewrite every production to use the universal tagset
if isinstance(production.lhs(), Nonterminal) and production.lhs().symbol() != 'S':
production._lhs = Nonterminal(tag.map_tag('en-ptb','universal',production.lhs().symbol()))
for elem in enumerate(production.rhs()):
if isinstance(elem, Nonterminal):
production._rhs[elem] = Nonterminal(tag.map_tag('en-ptb','universal', production.rhs()[elem].symbol()))
'''
S = Nonterminal('S')
grammar = induce_pcfg(S, productions) # induce PCFG from productions learned in treebank
# print(grammar)
return grammar
def test_PennCorpus():
from nltk.corpus import treebank
fileids = treebank.fileids()
ADJP_ProductionList = []
ADVP_ProductionList = []
NP_ProductionList = []
VP_ProductionList = []
for fileld in fileids:
trees = treebank.parsed_sents(fileld)
for tree in trees:
productions = tree.productions()
for production in productions:
if str(production.lhs()) == 'ADJP':
ADJP_ProductionList.append(production)
if str(production.lhs()) == 'ADVP':
ADVP_ProductionList.append(production)
if str(production.lhs()) == 'NP':
NP_ProductionList.append(production)
if str(production.lhs()) == 'VP':
VP_ProductionList.append(production)
print len(ADJP_ProductionList), len(ADVP_ProductionList), len(
NP_ProductionList), len(VP_ProductionList)
c_ADJP = Counter(ADJP_ProductionList)
c_ADVP = Counter(ADVP_ProductionList)
c_NP = Counter(NP_ProductionList)
c_VP = Counter(VP_ProductionList)
c_ADJP_sorted = sorted(c_ADJP.iteritems(),
key=lambda asd: asd[1],
reverse=True)
c_ADVP_sorted = sorted(c_ADVP.iteritems(),
key=lambda asd: asd[1],
reverse=True)
c_NP_sorted = sorted(c_NP.iteritems(),
key=lambda asd: asd[1],
reverse=True)
c_VP_sorted = sorted(c_VP.iteritems(),
key=lambda asd: asd[1],
reverse=True)
def train_pcfg():
print 'training grammar'
productions = []
# print len(treebank.fileids())
trees = []
# up to 199 less for shorter grammar for quicker training
for fileid in treebank.fileids()[0:20]:
for tree in treebank.parsed_sents(fileid):
# perform optional tree transformations, e.g.:
# Remove branches A->B->C into A->B+C so we can avoid infinite
# productions
tree.collapse_unary(collapsePOS=False)
# Remove A->(B,C,D) into A->B,C+D->D (binarization req'd by CKY parser)
# horizontal and vertical Markovization: remember parents and siblings in tree
# This gives a performance boost, but makes the grammar HUGE
# If we use these we would need to implement a tag forgetting method
#tree.chomsky_normal_form(horzMarkov = 0, vertMarkov=0)
tree.chomsky_normal_form()
productions += tree.productions()
S = nltk.Nonterminal('S')
grammar = nltk.induce_pcfg(S, productions)
print "grammar trained!"
return grammar
def main():
# train = treebank.fileids()[:190]
test = treebank.fileids()[190:] # 10 last sentences
# original grammar
# pcfg = induce_grammar(train)
# pickle.dump(pcfg, open("grammar.pcfg", 'wb'))
# load grammar
# pcfg : PCFG = pickle.load(open("grammar.pcfg", 'rb'))
# fill in missing words
# missing_words = get_missing_words(pcfg, test)
# pcfg_unk = fill_missing_words(pcfg, missing_words)
# pickle.dump(pcfg_unk, open("grammar_unk.pcfg", 'wb'))
# load unk grammar
pcfg_unk: PCFG = pickle.load(open("grammar_unk.pcfg", 'rb'))
# use unk grammar on test sentences
parser = ViterbiParser(pcfg_unk)
parse_treebank(parser, test)
def train_pcfg():
print 'training grammar'
productions = []
# print len(treebank.fileids())
trees = []
# up to 199 less for shorter grammar for quicker training
for fileid in treebank.fileids()[0:20]:
for tree in treebank.parsed_sents(fileid):
# perform optional tree transformations, e.g.:
# Remove branches A->B->C into A->B+C so we can avoid infinite
# productions
tree.collapse_unary(collapsePOS=False)
# Remove A->(B,C,D) into A->B,C+D->D (binarization req'd by CKY parser)
# horizontal and vertical Markovization: remember parents and siblings in tree
# This gives a performance boost, but makes the grammar HUGE
# If we use these we would need to implement a tag forgetting method
#tree.chomsky_normal_form(horzMarkov = 0, vertMarkov=0)
tree.chomsky_normal_form()
productions += tree.productions()
S = nltk.Nonterminal('S')
grammar = nltk.induce_pcfg(S, productions)
print "grammar trained!"
return grammar
def lab1():
# set this to your own feature extraction function
extractor = funtag_features.extract_features
# We reserve some treebank files for testing purposes.
# This shouldn't be touched until you have optimized your
# results on the development set.
td_files, test_files = train_test_split(treebank.fileids(),
train_size=0.8,
random_state=0)
# Split the rest into a training and a development set.
train_files, dev_files = train_test_split(td_files,
train_size=0.8,
random_state=0)
print('Reading training trees from treebank...')
X_train, Y_train = read_treebank_files(train_files, extractor,[])
print('Training classifier...')
classifier = train_scikit_classifier(X_train, Y_train)
print('Done training.')
print('Reading evaluation trees from treebank...')
X_eval, Y_eval = read_treebank_files(dev_files, extractor,[])
# When you have optimized your system for the development set,
# you can evaluate on the test set.
#X_eval, Y_eval = read_treebank_files(test_files, extractor, [])
print('Running classifier on evaluation data...')
Y_out = classifier.predict(X_eval)
print_stats(Y_eval, Y_out)
def perplexity():
'''
Give the PCFG and the parser used, run the parser on
the rest of the treebank and calculates the perplexity
of the model given the testing sentences.
'''
PCFG_grammar = make_PCFG_grammar()
parser = ViterbiParser(PCFG_grammar)
all_p = []
skipped_sentence = 0
for item in treebank.fileids()[1964:]:
trees = treebank.parsed_sents(item)
for tree in trees:
tree = tree.leaves()
try:
PCFG_grammar.check_coverage(tree)
for parse in parser.parse(tree):
parse_string = str(parse)
p = re.search(r"p=([^/]+)", parse_string).group(1)
p = p[:-1]
all_p.append(float(p))
except:
skipped_sentence += 1
continue
perplexity = 1
N = float(len(all_p))
for p in all_p:
perplexity = perplexity * (1/p)
perplexity = pow(perplexity, 1/float(N))
print("Perplexity:", perplexity)
print("All parse probabilities:", all_p)
print("Skipped sentences:", skipped_sentence)
print("PCFG grammar:", PCFG_grammar)
def main():
#getting all treebank files
files = treebank.fileids()
#grammar will be stored in dict
grammar = {}
for file in files:
trees = treebank.parsed_sents(file)
for tree in trees:
grammar = traverse_tree(tree, grammar)
cfg = get_grammar_series(grammar)
cfg.to_csv("cfg_instances.csv")
cfg.to_pickle('cfg_pickle.pickle')
pcfg = get_probabilities(grammar)
pcfg_series = get_grammar_series(pcfg)
pcfg_series.to_csv('problem_1_pcfg.csv')
files = []
def find_pronouns(tree):
pronouns = []
for child in tree:
if type(child) in [unicode, str] and child.lower() in PRONOUNS:
pronouns.append((child.lower(), None))
if isinstance(child, ParentedTree):
pronouns = pronouns + find_pronouns(child)
return pronouns
total = 0
for file in treebank.fileids():
stats['name'] = file
for tree in treebank.parsed_sents(file):
tree = ParentedTree.convert(tree)
for pronoun, np_node in find_pronouns(tree):
if pronoun in gendered:
stats['gendered'] += 1
if pronoun in itits:
stats['itits'] += 1
stats['total'] += 1
total += 1
stats['pct_gendered'] = stats['gendered']/float(stats['total'])
print file, total
files.append(stats.copy())
from nltk import ParentedTree, corpus
from nltk.corpus import treebank, names
import Queue
from collections import deque
from sys import argv
FILENAMES = [file for file in treebank.fileids()[:20]]
PRONOUNS = {'he': 'male', 'him': 'male', 'his': 'male', 'himself': 'male',
'she': 'female', 'her': 'female', 'hers': 'female', 'herself': 'female',
'they': 'plural', 'them': 'plural', 'their': 'plural', 'theirs': 'plural', 'themselves': 'plural',
'it': 'singular', 'its': 'singular', 'itself': 'singular'}
PRONOUN_RESULTS = {'male': 0, 'male_total':0, 'male_pct':0, 'female': 0, 'female_total': 0, 'female_pct':0,'neutral': 0,
'neutral_total': 0, 'neutral_pct':0, 'they': 0, 'they_total': 0, 'they_pct':0, 'reflexive': 0, 'reflexive_total': 0,
'reflexive_pct':0,}
NAMELIST = ([(name, "male") for name in names.words("male.txt")] +
[(name, "female") for name in names.words("female.txt")])
NOMINALS = {'NN': 'singular', 'NNS': 'plural', 'NNP': 'singular', 'NNPS': 'plural', 'PRP': 'singular'}
def update_pronoun_results(pronoun, correct):
if pronoun in ['he', 'him', 'his', 'himself']:
if correct:
PRONOUN_RESULTS['male'] += 1
else:
PRONOUN_RESULTS['male_total'] += 1
etiquette.
"""
return [(word, "NN") for word in sent]
# EVALUATION
import nltk
from nltk.corpus import treebank
training_size = 150
development_size = 25
training_data = list(treebank.tagged_sents(treebank.fileids()[:training_size]))
development_data = list(treebank.tagged_sents(treebank.fileids()[training_size : training_size + development_size]))
def flatten(lol):
"""A partir d'une liste des listes des valeurs, produit une liste des
simple valeurs en concatenant les listes."""
return [value for l in lol for value in l]
def filter_text(corpus):
return [[(word, tag) for (word, tag) in sent if tag != '-NONE-'] \
for sent in corpus]
def measure_accuracy():
"""Mesure l'efficacite de votre approche en comptant la proportion
des mots pour lesquels la bonne etiquette ete recuperee par votre
algorithme."""
if mytree:
print("parsed!", mytree)
original_trees += [tree]
resulting_trees += [mytree]
else:
print("didn't parse")
unsuccessful_parses += 1
if original_trees:
# If we got some successful parses, evaluate these:
accuracy = evalb.evalb(resulting_trees, original_trees)
count = len(original_trees)
if verbose:
print("In fold", i, "we parsed", count, "sentences with an accuracy of", accuracy)
# Update the count and averages
avg_accuracy = (avg_accuracy*parsed_num + accuracy*count)
parsed_num += count
avg_accuracy /= parsed_num
unparsed_num += unsuccessful_parses
# Aggregate results.
if verbose:
print("We parsed", parsed_num, "sentences with an accuracy of", avg_accuracy)
print("We could not parse", unparsed_num, "sentences")
return avg_accuracy
print(cross_validate(fileids=treebank.fileids()[:25], verbose=True))
else:
for i in tree:
topresent(i, tree)
def halflemmatize(word):
if word in ['fell', 'fallen']:
return 'fall'
if word in ['is', 'was']:
return 'is'
elif word in ['are', 'were', '\'re']:
return 'are'
elif word in ['\'m', 'am']:
return 'am'
elif word in ['\'S', '\'s']:
return 'is'
out = wnl.lemmatize(word.lower(), 'v')
return out
if __name__ == "__main__":
count = 0
for file in treebank.fileids():
for i in treebank.parsed_sents(file):
print(i.leaves())
if i.leaves()[0] == 'These' and i.leaves()[1] == 'three':
print(i)
tofuture(i, Tree('None', []))
print(i.leaves())
count += 1