mtgencode/lib/cbow.py
2016-08-13 21:16:43 -04:00

197 lines
6.3 KiB
Python

# Infinite thanks to Talcos from the mtgsalvation forums, who among
# many, many other things wrote the original version of this code.
# I have merely ported it to fit my needs.
import re
import sys
import subprocess
import os
import struct
import math
import multiprocessing
import utils
import cardlib
import transforms
import namediff
libdir = os.path.dirname(os.path.realpath(__file__))
datadir = os.path.realpath(os.path.join(libdir, '../data'))
# multithreading control parameters
cores = multiprocessing.cpu_count()
# max length of vocabulary entries
max_w = 50
#### snip! ####
def read_vector_file(fname):
with open(fname, 'rb') as f:
words = int(f.read(4))
size = int(f.read(4))
vocab = [' '] * (words * max_w)
M = []
for b in range(0,words):
a = 0
while True:
c = f.read(1)
vocab[b * max_w + a] = c;
if len(c) == 0 or c == ' ':
break
if (a < max_w) and vocab[b * max_w + a] != '\n':
a += 1
tmp = list(struct.unpack('f'*size,f.read(4 * size)))
length = math.sqrt(sum([tmp[i] * tmp[i] for i in range(0,len(tmp))]))
for i in range(0,len(tmp)):
tmp[i] /= length
M.append(tmp)
return ((''.join(vocab)).split(),M)
def makevector(vocabulary,vecs,sequence):
words = sequence.split()
indices = []
for word in words:
if word not in vocabulary:
#print("Missing word in vocabulary: " + word)
continue
#return [0.0]*len(vecs[0])
indices.append(vocabulary.index(word))
#res = map(sum,[vecs[i] for i in indices])
res = None
for v in [vecs[i] for i in indices]:
if res == None:
res = v
else:
res = [x + y for x, y in zip(res,v)]
# bad things happen if we have a vector of only unknown words
if res is None:
return [0.0]*len(vecs[0])
length = math.sqrt(sum([res[i] * res[i] for i in range(0,len(res))]))
for i in range(0,len(res)):
res[i] /= length
return res
#### !snip ####
try:
import numpy
def cosine_similarity(v1,v2):
A = numpy.array([v1,v2])
# from http://stackoverflow.com/questions/17627219/whats-the-fastest-way-in-python-to-calculate-cosine-similarity-given-sparse-mat
# base similarity matrix (all dot products)
# replace this with A.dot(A.T).todense() for sparse representation
similarity = numpy.dot(A, A.T)
# squared magnitude of preference vectors (number of occurrences)
square_mag = numpy.diag(similarity)
# inverse squared magnitude
inv_square_mag = 1 / square_mag
# if it doesn't occur, set it's inverse magnitude to zero (instead of inf)
inv_square_mag[numpy.isinf(inv_square_mag)] = 0
# inverse of the magnitude
inv_mag = numpy.sqrt(inv_square_mag)
# cosine similarity (elementwise multiply by inverse magnitudes)
cosine = similarity * inv_mag
cosine = cosine.T * inv_mag
return cosine[0][1]
except ImportError:
def cosine_similarity(v1,v2):
#compute cosine similarity of v1 to v2: (v1 dot v1)/{||v1||*||v2||)
sumxx, sumxy, sumyy = 0, 0, 0
for i in range(len(v1)):
x = v1[i]; y = v2[i]
sumxx += x*x
sumyy += y*y
sumxy += x*y
return sumxy/math.sqrt(sumxx*sumyy)
def cosine_similarity_name(cardvec, v, name):
return (cosine_similarity(cardvec, v), name)
# we need to put the logic in a regular function (as opposed to a method of an object)
# so that we can pass the function to multiprocessing
def f_nearest(card, vocab, vecs, cardvecs, n):
if isinstance(card, cardlib.Card):
words = card.vectorize().split('\n\n')[0]
else:
# assume it's a string (that's already a vector)
words = card
if not words:
return []
cardvec = makevector(vocab, vecs, words)
comparisons = [cosine_similarity_name(cardvec, v, name) for (name, v) in cardvecs]
comparisons.sort(reverse = True)
comp_n = comparisons[:n]
if isinstance(card, cardlib.Card) and card.bside:
comp_n += f_nearest(card.bside, vocab, vecs, cardvecs, n=n)
return comp_n
def f_nearest_per_thread(workitem):
(workcards, vocab, vecs, cardvecs, n) = workitem
return [f_nearest(card, vocab, vecs, cardvecs, n) for card in workcards]
class CBOW:
def __init__(self, verbose = True,
vector_fname = os.path.join(datadir, 'cbow.bin'),
card_fname = os.path.join(datadir, 'output.txt')):
self.verbose = verbose
self.cardvecs = []
if self.verbose:
print('Building a cbow model...')
if self.verbose:
print(' Reading binary vector data from: ' + vector_fname)
(vocab, vecs) = read_vector_file(vector_fname)
self.vocab = vocab
self.vecs = vecs
if self.verbose:
print(' Reading encoded cards from: ' + card_fname)
print(
' They\'d better be in the same order as the file used to build the vector model!')
with open(card_fname, 'rt') as f:
text = f.read()
for card_src in text.split(utils.cardsep):
if card_src:
card = cardlib.Card(card_src)
name = card.name
self.cardvecs += [(name, makevector(self.vocab,
self.vecs,
card.vectorize()))]
if self.verbose:
print('... Done.')
print(' vocab size: ' + str(len(self.vocab)))
print(' raw vecs: ' + str(len(self.vecs)))
print(' card vecs: ' + str(len(self.cardvecs)))
def nearest(self, card, n=5):
return f_nearest(card, self.vocab, self.vecs, self.cardvecs, n)
def nearest_par(self, cards, n=5, threads=cores):
workpool = multiprocessing.Pool(threads)
proto_worklist = namediff.list_split(cards, threads)
worklist = [(x, self.vocab, self.vecs, self.cardvecs, n)
for x in proto_worklist]
donelist = workpool.map(f_nearest_per_thread, worklist)
return namediff.list_flatten(donelist)