def test():
"""
A test to check if the changes I made have the intended
effect
"""
import nltk
from nltk.parse import ViterbiParser
sent = 'I saw the man with my telescope'
tokens = sent.split()
grammar = nltk.toy_pcfg1
parser = ViterbiParser(grammar)
parser.trace(3)
parses = parser.nbest_parse(tokens)
print(parses)
def test(): """ A test to check if the changes I made have the intended effect """ import nltk from nltk.parse import ViterbiParser sent = 'I saw the man with my telescope' tokens = sent.split() grammar = nltk.toy_pcfg1 parser = ViterbiParser(grammar) parser.trace(3) parses = parser.nbest_parse(tokens) print(parses)
def demo():
"""
A demonstration of the probabilistic parsers. The user is
prompted to select which demo to run, and how many parses should
be found; and then each parser is run on the same demo, and a
summary of the results are displayed.
"""
import sys, time
import nltk
from nltk import tokenize
from nltk.parse import ViterbiParser
# Define two demos. Each demo has a sentence and a grammar.
demos = [('I saw the man with my telescope', nltk.toy_pcfg1),
('the boy saw Jack with Bob under the table with a telescope', nltk.toy_pcfg2)]
# Ask the user which demo they want to use.
print
for i in range(len(demos)):
print '%3s: %s' % (i+1, demos[i][0])
print ' %r' % demos[i][1]
print
print 'Which demo (%d-%d)? ' % (1, len(demos)),
try:
snum = int(sys.stdin.readline().strip())-1
sent, grammar = demos[snum]
except:
print 'Bad sentence number'
return
# Tokenize the sentence.
tokens = sent.split()
parser = ViterbiParser(grammar)
all_parses = {}
print '\nsent: %s\nparser: %s\ngrammar: %s' % (sent,parser,grammar)
parser.trace(3)
t = time.time()
parses = parser.nbest_parse(tokens)
time = time.time()-t
if parses:
average = reduce(lambda a,b:a+b.prob(), parses, 0)/len(parses)
else:
average = 0
num_parses = len(parses)
for p in parses:
all_parses[p.freeze()] = 1
# Print some summary statistics
print
print 'Time (secs) # Parses Average P(parse)'
print '-----------------------------------------'
print '%11.4f%11d%19.14f' % (time, num_parses, average)
parses = all_parses.keys()
if parses:
p = reduce(lambda a,b:a+b.prob(), parses, 0)/len(parses)
else: p = 0
print '------------------------------------------'
print '%11s%11d%19.14f' % ('n/a', len(parses), p)
# Ask the user if we should draw the parses.
print
print 'Draw parses (y/n)? ',
if sys.stdin.readline().strip().lower().startswith('y'):
from nltk.draw.tree import draw_trees
print ' please wait...'
draw_trees(*parses)
# Ask the user if we should print the parses.
print
print 'Print parses (y/n)? ',
if sys.stdin.readline().strip().lower().startswith('y'):
for parse in parses:
print parse
def demo():
"""
A demonstration of the probabilistic parsers. The user is
prompted to select which demo to run, and how many parses should
be found; and then each parser is run on the same demo, and a
summary of the results are displayed.
"""
import sys, time
import nltk
from nltk import tokenize
from nltk.parse import ViterbiParser
# Define two demos. Each demo has a sentence and a grammar.
demos = [('I saw the man with my telescope', nltk.toy_pcfg1),
('the boy saw Jack with Bob under the table with a telescope', nltk.toy_pcfg2)]
# Ask the user which demo they want to use.
print
for i in range(len(demos)):
print '%3s: %s' % (i+1, demos[i][0])
print ' %r' % demos[i][1]
print
print 'Which demo (%d-%d)? ' % (1, len(demos)),
try:
snum = int(sys.stdin.readline().strip())-1
sent, grammar = demos[snum]
except:
print 'Bad sentence number'
return
# Tokenize the sentence.
tokens = sent.split()
parser = ViterbiParser(grammar)
all_parses = {}
print '\nsent: %s\nparser: %s\ngrammar: %s' % (sent,parser,grammar)
parser.trace(3)
t = time.time()
parses = parser.nbest_parse(tokens)
time = time.time()-t
average = (reduce(lambda a,b:a+b.prob(), parses, 0)/len(parses)
if parses else 0)
num_parses = len(parses)
for p in parses:
all_parses[p.freeze()] = 1
# Print some summary statistics
print
print 'Time (secs) # Parses Average P(parse)'
print '-----------------------------------------'
print '%11.4f%11d%19.14f' % (time, num_parses, average)
parses = all_parses.keys()
if parses:
p = reduce(lambda a,b:a+b.prob(), parses, 0)/len(parses)
else: p = 0
print '------------------------------------------'
print '%11s%11d%19.14f' % ('n/a', len(parses), p)
# Ask the user if we should draw the parses.
print
print 'Draw parses (y/n)? ',
if sys.stdin.readline().strip().lower().startswith('y'):
from nltk.draw.tree import draw_trees
print ' please wait...'
draw_trees(*parses)
# Ask the user if we should print the parses.
print
print 'Print parses (y/n)? ',
if sys.stdin.readline().strip().lower().startswith('y'):
for parse in parses:
print parse
