A-M baby

Task/Inverted-index/Python/inverted-index-1.py

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+'''
+This implements: http://en.wikipedia.org/wiki/Inverted_index of 28/07/10
+'''
+
+from pprint import pprint as pp
+from glob import glob
+try: reduce
+except: from functools import reduce
+try:    raw_input
+except: raw_input = input
+
+
+def parsetexts(fileglob='InvertedIndex/T*.txt'):
+    texts, words = {}, set()
+    for txtfile in glob(fileglob):
+        with open(txtfile, 'r') as f:
+            txt = f.read().split()
+            words |= set(txt)
+            texts[txtfile.split('\\')[-1]] = txt
+    return texts, words
+
+def termsearch(terms): # Searches simple inverted index
+    return reduce(set.intersection,
+                  (invindex[term] for term in terms),
+                  set(texts.keys()))
+
+texts, words = parsetexts()
+print('\nTexts')
+pp(texts)
+print('\nWords')
+pp(sorted(words))
+
+invindex = {word:set(txt
+                        for txt, wrds in texts.items() if word in wrds)
+            for word in words}
+print('\nInverted Index')
+pp({k:sorted(v) for k,v in invindex.items()})
+
+terms = ["what", "is", "it"]
+print('\nTerm Search for: ' + repr(terms))
+pp(sorted(termsearch(terms)))