def tercom_scores_unicode(hypotheses, references):
"""
Returns a list of TERCOM scores
"""
writer = codecs.getwriter('utf-8')
with NamedTemporaryFile('w') as hypothesis_file, NamedTemporaryFile('w') as reference_file:
hypothesis_file = writer(hypothesis_file)
reference_file = writer(reference_file)
for i, (hypothesis, reference) in enumerate(zip(hypotheses, references)):
hypothesis_file.write(u'{} ({})\n'.format(hypothesis, i))
reference_file.write(u'{} ({})\n'.format(reference, i))
hypothesis_file.flush()
reference_file.flush()
filename = mktemp()
cmd = ['java', '-jar', 'tercom.jar', '-h', hypothesis_file.name, '-r', reference_file.name,
'-o', 'ter', '-n', filename]
output = uopen('/dev/null', 'w')
call(cmd, stdout=output, stderr=output)
with uopen(filename + '.ter') as f:
lines = list(f)
scores = [float(line.split(' ')[-1]) for line in lines[2:]]
os.remove(filename + '.ter')
return scores
def extract_from_ibm(filename1, filename2):
"""
Takes two GIZA++ alignment file (first file is source->target, second file is target->source),
and yields trajectories.
"""
with uopen(filename1) as file1, uopen(filename2) as file2:
for line1, line2 in zip(islice(file1, 2, None, 3),
islice(file2, 2, None, 3)):
pairs1, words1 = get_pairs(line1.strip())
pairs2, words2 = get_pairs(line2.strip())
pairs2 = [pair[::-1] for pair in pairs2]
sentence = ' '.join(words1)
intersection = list(set(pairs1).intersection(set(pairs2)))
ops = []
pairs = intersection[:]
pairs.append((len(words1), len(words2)))
i = 0
while i < len(words2):
x = next((x for x, y in pairs if y == i), None)
if not any(s == i for s, _ in pairs):
ops.append(('DEL', i))
del words1[i]
pairs = [(k - int(i < k), l) for k, l in pairs]
elif x == i:
if words1[i] != words2[i]:
ops.append(('SUB', i, words2[i]))
pairs.remove((i, i))
words1[i] = words2[i]
i += 1
elif x is not None:
# move
# TODO: fix
ops.append(('MOVE', x, i))
words1.insert(i, words1.pop(x))
pairs = [(i, l) if k == x and l == i else
(k + int(i <= k < x), l) for k, l in pairs]
else:
# insertion
ops.append(('INS', i, words2[i]))
words1.insert(i, words2[i])
pairs = [(k + int(i <= k), l) for k, l in pairs]
i += 1
ops.append(('STOP', ))
yield sentence, ops
def read_trajectories(filename):
"""
A trajectory file contains entries each corresponding to a transition, whose
fields are delimited by '|||'.
Transitions contain those fields: id, src, s, s', a, score(s), score(s')
The first field is the id of this transition's trajectory.
"""
trajectories = []
with uopen(filename) as f:
current_idx = None
current_traj = []
for line in f:
idx, src, trg1, trg2, action, score1, score2 = line.split(
'|||')
score1, score2 = float(score1), float(score2)
action = action.split()
op = action[0]
if op in ['SUB', 'INS', 'DEL']:
action[1] = int(action[1])
elif op == 'MOVE':
action[1:] = map(int, action[1:])
elif op != 'STOP':
raise Exception('Unknown action type')
action = tuple(action)
# a state is a pair (source sentence, translation hypothesis)
# source sentence is the same for all transitions in a given trajectory
state1 = State(src, trg1)
state2 = State(src, trg2)
transition = (state1, state2, action, score1, score2)
# a different index marks the end of a trajectory
if current_idx is not None and idx != current_idx:
trajectories.append(current_traj)
current_traj = []
current_traj.append(transition)
current_idx = idx
return trajectories
def read_trajectories(filename):
"""
A trajectory file contains entries each corresponding to a transition, whose
fields are delimited by '|||'.
Transitions contain those fields: id, src, s, s', a, score(s), score(s')
The first field is the id of this transition's trajectory.
"""
trajectories = []
with uopen(filename) as f:
current_idx = None
current_traj = []
for line in f:
idx, src, trg1, trg2, action, score1, score2 = line.split('|||')
score1, score2 = float(score1), float(score2)
action = action.split()
op = action[0]
if op in ['SUB', 'INS', 'DEL']:
action[1] = int(action[1])
elif op == 'MOVE':
action[1:] = map(int, action[1:])
elif op != 'STOP':
raise Exception('Unknown action type')
action = tuple(action)
# a state is a pair (source sentence, translation hypothesis)
# source sentence is the same for all transitions in a given trajectory
state1 = State(src, trg1)
state2 = State(src, trg2)
transition = (state1, state2, action, score1, score2)
# a different index marks the end of a trajectory
if current_idx is not None and idx != current_idx:
trajectories.append(current_traj)
current_traj = []
current_traj.append(transition)
current_idx = idx
return trajectories
def extract_from_ter(ter_filename, src_filename):
"""
Yields trajectories (lists of operations):
SUB index word
DEL index
INS index word
MOVE index position
operations are applied from left to right (indices refer to the current state of the hypothesis)
"""
with uopen(ter_filename) as f, uopen(src_filename) as src_file:
while True:
src_sent = next(src_file).strip()
ops = []
lines = list(takewhile(lambda line: line.strip(), f))
if not lines:
break
ref = re.match(r'Original Ref:\s*(.*?)\n', lines[1]).group(1)
hyp = re.match(r'Original Hyp:\s*(.*?)\n', lines[2]).group(1)
hyp_after_shift = re.match(r'Hyp After Shift:\s*(.*?)\n',
lines[3]).group(1)
align = re.match(r'Alignment:\s*\((.*?)\)', lines[4]).group(1)
numshifts = int(re.match(r'NumShifts: (\d+)', lines[5]).group(1))
regex = re.compile(r'\s*\[(\d+), (\d+), .*?/(.*?)\] \(\[(.*?)\]\)')
shifts = [
regex.match(lines[6 + i]).groups() for i in range(numshifts)
]
shifts = [(int(i), int(j), int(k), re.sub(r',\s+', ' ', words))
for i, j, k, words in shifts]
shift_indices = get_shifts(shifts, hyp.split(),
hyp_after_shift.split())
for i, j, k in shift_indices:
l = j - i
for x in range(l):
if k >= i:
op = ('MOVE', i, k + l - 1)
else:
op = ('MOVE', i + x, k + x)
ops.append(op)
ref_iter = iter(ref.split())
hyp_iter = iter(hyp_after_shift.split())
i = 0
for op in align:
# insert and delete are reversed in TERCOM
if op != 'D':
next(hyp_iter)
if op != 'I':
inserted = next(ref_iter)
if op == 'S':
ops.append(('SUB', i, inserted))
elif op == 'D':
ops.append(('INS', i, inserted))
elif op == 'I':
ops.append(('DEL', i))
i -= 1
i += 1
ops.append(('STOP', ))
# try to reconstruct reference
state = State(src_sent, hyp)
for op in ops:
state = state.transition(op)
if state.trg != ref: # in some weird and rare cases (likely due to a bug in TERCOM)
yield (src_sent, hyp), [
] # empty trajectory (index is skipped in the output)
continue
#assert(state.trg == ref)
yield (src_sent, hyp), ops
