X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;f=language_models.py;h=62219efe54ab2ad20e07c1838d5ade29e6511d7d;hb=ae4400046f558cbea84662a0159d13bfa9cbb569;hp=59d858868dd5b67d5de9dd848fe26d6b5f1c6391;hpb=9ab85aeac37f3ceada3d7d959a7f5ef8835638f5;p=cipher-training.git diff --git a/language_models.py b/language_models.py index 59d8588..62219ef 100644 --- a/language_models.py +++ b/language_models.py @@ -1,6 +1,10 @@ +"""Language-specific functions, including models of languages based on data of +its use. +""" + import string -import norms import random +import norms import collections import unicodedata import itertools @@ -16,7 +20,7 @@ def letters(text): return ''.join([c for c in text if c in string.ascii_letters]) def unaccent(text): - """Remove all accents from letters. + """Remove all accents from letters. It does this by converting the unicode string to decomposed compatability form, dropping all the combining accents, then re-encoding the bytes. @@ -37,7 +41,7 @@ def unaccent(text): def sanitise(text): """Remove all non-alphabetic characters and convert the text to lowercase - + >>> sanitise('The Quick') 'thequick' >>> sanitise('The Quick BROWN fox jumped! over... the (9lazy) DOG') @@ -72,30 +76,30 @@ with open('words.txt', 'r') as f: def weighted_choice(d): - """Generate random item from a dictionary of item counts - """ - target = random.uniform(0, sum(d.values())) - cuml = 0.0 - for (l, p) in d.items(): - cuml += p - if cuml > target: - return l - return None + """Generate random item from a dictionary of item counts + """ + target = random.uniform(0, sum(d.values())) + cuml = 0.0 + for (l, p) in d.items(): + cuml += p + if cuml > target: + return l + return None def random_english_letter(): - """Generate a random letter based on English letter counts - """ - return weighted_choice(normalised_english_counts) + """Generate a random letter based on English letter counts + """ + return weighted_choice(normalised_english_counts) def ngrams(text, n): """Returns all n-grams of a text >>> ngrams(sanitise('the quick brown fox'), 2) # doctest: +NORMALIZE_WHITESPACE - ['th', 'he', 'eq', 'qu', 'ui', 'ic', 'ck', 'kb', 'br', 'ro', 'ow', 'wn', + ['th', 'he', 'eq', 'qu', 'ui', 'ic', 'ck', 'kb', 'br', 'ro', 'ow', 'wn', 'nf', 'fo', 'ox'] >>> ngrams(sanitise('the quick brown fox'), 4) # doctest: +NORMALIZE_WHITESPACE - ['theq', 'hequ', 'equi', 'quic', 'uick', 'ickb', 'ckbr', 'kbro', 'brow', + ['theq', 'hequ', 'equi', 'quic', 'uick', 'ickb', 'ckbr', 'kbro', 'brow', 'rown', 'ownf', 'wnfo', 'nfox'] """ return [text[i:i+n] for i in range(len(text)-n+1)] @@ -125,30 +129,29 @@ Pl = Pdist(datafile('count_1l.txt'), lambda _k, _N: 0) P2l = Pdist(datafile('count_2l.txt'), lambda _k, _N: 0) P3l = Pdist(datafile('count_3l.txt'), lambda _k, _N: 0) -def Pwords(words): +def Pwords(words): """The Naive Bayes log probability of a sequence of words. """ return sum(Pw[w.lower()] for w in words) -def Pwords_wrong(words): +def Pwords_wrong(words): """The Naive Bayes log probability of a sequence of words. """ return sum(Pw_wrong[w.lower()] for w in words) - def Pletters(letters): """The Naive Bayes log probability of a sequence of letters. """ return sum(Pl[l.lower()] for l in letters) def Pbigrams(letters): - """The Naive Bayes log probability of the bigrams formed from a sequence + """The Naive Bayes log probability of the bigrams formed from a sequence of letters. """ return sum(P2l[p] for p in ngrams(letters, 2)) def Ptrigrams(letters): - """The Naive Bayes log probability of the trigrams formed from a sequence + """The Naive Bayes log probability of the trigrams formed from a sequence of letters. """ return sum(P3l[p] for p in ngrams(letters, 3)) @@ -161,8 +164,8 @@ def cosine_similarity_score(text): >>> cosine_similarity_score('abcabc') # doctest: +ELLIPSIS 0.26228882... """ - return norms.cosine_similarity(english_counts, - collections.Counter(sanitise(text))) + return norms.cosine_similarity(english_counts, + collections.Counter(sanitise(text))) if __name__ == "__main__":