Fixed typo in docstring
[cipher-tools.git] / find_best_caesar_break_parameters.py
index 711cff0f5a3fbe7a10bcdc413da212b564700578..7a8ddc9dc0a4dd3340a84c3fb021d44131d1ab87 100644 (file)
@@ -1,60 +1,80 @@
 import random
+import collections
 from cipher import *
+from cipherbreak import *
+import itertools
+import csv
 
-
-corpus = sanitise(''.join([open('shakespeare.txt', 'r').read(), open('sherlock-holmes.txt', 'r').read(), open('war-and-peace.txt', 'r').read()]))
+corpus = sanitise(''.join([open('shakespeare.txt', 'r').read(), 
+    open('sherlock-holmes.txt', 'r').read(), 
+    open('war-and-peace.txt', 'r').read()]))
 corpus_length = len(corpus)
 
-scaled_english_counts = norms.scale(english_counts)
+euclidean_scaled_english_counts = norms.euclidean_scale(english_counts)
+
+metrics = [{'func': norms.l1, 'invert': True, 'name': 'l1'}, 
+    {'func': norms.l2, 'invert': True, 'name': 'l2'},
+    {'func': norms.l3, 'invert': True, 'name': 'l3'},
+    {'func': norms.cosine_similarity, 'invert': False, 'name': 'cosine_similarity'}]
+    # {'func': norms.harmonic_mean, 'invert': True, 'name': 'harmonic_mean'},
+    # {'func': norms.geometric_mean, 'invert': True, 'name': 'geometric_mean'}]
+scalings = [{'corpus_frequency': normalised_english_counts, 
+         'scaling': norms.normalise,
+         'name': 'normalised'},
+        {'corpus_frequency': euclidean_scaled_english_counts, 
+         'scaling': norms.euclidean_scale,
+         'name': 'euclidean_scaled'}]
+message_lengths = [100, 50, 30, 20, 10, 5]
 
+trials = 5000
 
-metrics = [norms.l1, norms.l2, norms.l3, norms.cosine_distance, norms.harmonic_mean, norms.geometric_mean]
-corpus_frequencies = [normalised_english_counts, scaled_english_counts]
-scalings = [norms.normalise, norms.scale]
-message_lengths = [3000, 1000, 300, 100, 50, 30, 20, 10, 5]
+scores = {}
 
-metric_names = ['l1', 'l2', 'l3', 'cosine_distance', 'harmonic_mean', 'geometric_mean']
-corpus_frequency_names = ['normalised_english_counts', 'scaled_english_counts']
-scaling_names = ['normalise', 'scale']
 
-trials = 5000
+def make_frequency_compare_function(target_frequency, frequency_scaling, metric, invert):
+    def frequency_compare(text):
+        counts = frequency_scaling(frequencies(text))
+        if invert:
+            score = -1 * metric(target_frequency, counts)
+        else:
+            score = metric(target_frequency, counts)
+        return score
+    return frequency_compare
+
+def scoring_functions():
+    return [{'func': make_frequency_compare_function(s['corpus_frequency'], 
+                s['scaling'], m['func'], m['invert']),
+            'name': '{} + {}'.format(m['name'], s['name'])}
+        for m in metrics
+        for s in scalings] + [{'func': Pletters, 'name': 'Pletters'}]
+
+def eval_scores():
+    [eval_one_score(f, l) 
+        for f in scoring_functions()
+        for l in message_lengths]
+
+def eval_one_score(scoring_function, message_length):
+    print(scoring_function['name'], message_length)
+    if scoring_function['name'] not in scores:
+        scores[scoring_function['name']] = collections.defaultdict(int)
+    for _ in range(trials):
+        sample_start = random.randint(0, corpus_length - message_length)
+        sample = corpus[sample_start:(sample_start + message_length)]
+        key = random.randint(1, 25)
+        ciphertext = caesar_encipher(sample, key)
+        found_key, _ = caesar_break(ciphertext, scoring_function['func'])
+        if found_key == key:
+            scores[scoring_function['name']][message_length] += 1 
+    return scores[scoring_function['name']][message_length]
+
+def show_results():
+    with open('caesar_break_parameter_trials.csv', 'w') as f:
+        writer = csv.DictWriter(f, ['name'] + message_lengths, 
+            quoting=csv.QUOTE_NONNUMERIC)
+        writer.writeheader()
+        for scoring in sorted(scores):
+            scores[scoring]['name'] = scoring
+            writer.writerow(scores[scoring])
 
-scores = collections.defaultdict(int)
-for metric in range(len(metrics)):
-    scores[metric_names[metric]] = collections.defaultdict(int)
-    for corpus_freqency in range(len(corpus_frequencies)):
-        scores[metric_names[metric]][corpus_frequency_names[corpus_freqency]] = collections.defaultdict(int)
-        for scaling in range(len(scalings)):
-            scores[metric_names[metric]][corpus_frequency_names[corpus_freqency]][scaling_names[scaling]] = collections.defaultdict(int)
-            for message_length in message_lengths:
-                for i in range(trials):
-                    sample_start = random.randint(0, corpus_length - message_length)
-                    sample = corpus[sample_start:(sample_start + message_length)]
-                    key = random.randint(1, 25)
-                    sample_ciphertext = caesar_encipher(sample, key)
-                    (found_key, score) = caesar_break(sample_ciphertext, 
-                                                      metric=metrics[metric], 
-                                                      target_frequencies=corpus_frequencies[corpus_freqency], 
-                                                      message_frequency_scaling=scalings[scaling])
-                    if found_key == key:
-                        scores[metric_names[metric]][corpus_frequency_names[corpus_freqency]][scaling_names[scaling]][message_length] += 1 
-                print(', '.join([metric_names[metric], 
-                                 corpus_frequency_names[corpus_freqency], 
-                                 scaling_names[scaling], 
-                                 str(message_length), 
-                                 str(scores[metric_names[metric]][corpus_frequency_names[corpus_freqency]][scaling_names[scaling]][message_length] / trials) ]))
-
-
-with open('caesar_break_parameter_trials.csv', 'w') as f:
-    for metric in range(len(metrics)):
-        for corpus_freqency in range(len(corpus_frequencies)):
-            for scaling in range(len(scalings)):
-                for message_length in message_lengths:
-                    print(', '.join([metric_names[metric], 
-                                     corpus_frequency_names[corpus_freqency], 
-                                     scaling_names[scaling], 
-                                     str(message_length), 
-                                     str(scores[metric_names[metric]][corpus_frequency_names[corpus_freqency]][scaling_names[scaling]][message_length] / trials) ]), 
-                          file=f)
-                      
-                            
\ No newline at end of file
+eval_scores()
+show_results()