def index_processed_file(index, writer):
datafile = os.path.join(GPFS_STORAGE, "gram2_%s.processed" % str(index))
with open(datafile, 'r') as f:
pos = 0
line = f.readline()
while True:
if is_parent_line(line):
word, skip_lines, _ = parse_parent_line(line)
starting_pos = pos
md5 = hashlib.md5()
md5.update(word)
word_hash = md5.hexdigest()
for i in range(0, skip_lines):
f.readline()
chunk_size = f.tell() - starting_pos
index_entry = IndexEntry(word_hash, index, starting_pos, chunk_size)
writer.write(index_entry.pack())
pos = f.tell()
else:
if line == '':
break # last line is empty in the data file, we are done here
else:
raise ValueError('Improper data file %s' % datafile)
line = f.readline()
def extract_parent_word(index, starting, chunk_size):
datafile = os.path.join(GPFS_STORAGE, "gram2_%s.processed" % str(index))
with open(datafile, 'r') as df:
df.seek(starting)
lines = df.read(chunk_size).split("\n")
line = lines[0]
if not is_parent_line(line):
return None
parent_word, _, counts = parse_parent_line(lines[0])
return parent_word
def create_filter(datafile, force=False):
assert os.path.isfile(datafile)
datadir, datafilename = os.path.split(datafile)
filter_file = os.path.join(datadir, datafilename + ".filter")
if force or not os.path.isfile(filter_file):
bf = BloomFilter(capacity=1e6)
with open(datafile) as df:
line = next(df)
try:
while True:
if is_parent_line(line):
word, skips, _ = parse_parent_line(line)
bf.add(word)
for i in xrange(1, skips):
next(df)
line = next(df)
except StopIteration:
with open(filter_file, 'w') as ff:
bf.tofile(ff)
del bf
print("%s done." % filter_file)