Merged revisions 75339 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r75339 | georg.brandl | 2009-10-11 10:39:16 +0200 (So, 11 Okt 2009) | 1 line

  Update markov demo.
........

Demo/scripts/markov.py

@@ -5,11 +5,10 @@ class Markov:
         self.histsize = histsize
         self.choice = choice
         self.trans = {}
+
     def add(self, state, next):
-        if state not in self.trans:
-            self.trans[state] = [next]
-        else:
-            self.trans[state].append(next)
+        self.trans.setdefault(state, []).append(next)
+
     def put(self, seq):
         n = self.histsize
         add = self.add
@@ -17,26 +16,29 @@ class Markov:
         for i in range(len(seq)):
             add(seq[max(0, i-n):i], seq[i:i+1])
         add(seq[len(seq)-n:], None)
+
     def get(self):
         choice = self.choice
         trans = self.trans
         n = self.histsize
         seq = choice(trans[None])
-        while 1:
+        while True:
             subseq = seq[max(0, len(seq)-n):]
             options = trans[subseq]
             next = choice(options)
-            if not next: break
-            seq = seq + next
+            if not next:
+                break
+            seq += next
         return seq
 
+
 def test():
-    import sys, string, random, getopt
+    import sys, random, getopt
     args = sys.argv[1:]
     try:
-        opts, args = getopt.getopt(args, '0123456789cdw')
+        opts, args = getopt.getopt(args, '0123456789cdwq')
     except getopt.error:
-        print('Usage: markov [-#] [-cddqw] [file] ...')
+        print('Usage: %s [-#] [-cddqw] [file] ...' % sys.argv[0])
         print('Options:')
         print('-#: 1-digit history size (default 2)')
         print('-c: characters (default)')
@@ -49,16 +51,19 @@ def test():
         print('exactly one space separating words.')
         print('Output consists of paragraphs separated by blank')
         print('lines, where lines are no longer than 72 characters.')
+        sys.exit(2)
     histsize = 2
-    do_words = 0
+    do_words = False
     debug = 1
     for o, a in opts:
-        if '-0' <= o <= '-9': histsize = eval(o[1:])
-        if o == '-c': do_words = 0
-        if o == '-d': debug = debug + 1
+        if '-0' <= o <= '-9': histsize = int(o[1:])
+        if o == '-c': do_words = False
+        if o == '-d': debug += 1
         if o == '-q': debug = 0
-        if o == '-w': do_words = 1
-    if not args: args = ['-']
+        if o == '-w': do_words = True
+    if not args:
+        args = ['-']
+
     m = Markov(histsize, random.choice)
     try:
         for filename in args:
@@ -72,13 +77,15 @@ def test():
             if debug: print('processing', filename, '...')
             text = f.read()
             f.close()
-            paralist = string.splitfields(text, '\n\n')
+            paralist = text.split('\n\n')
             for para in paralist:
                 if debug > 1: print('feeding ...')
-                words = string.split(para)
+                words = para.split()
                 if words:
-                    if do_words: data = tuple(words)
-                    else: data = string.joinfields(words, ' ')
+                    if do_words:
+                        data = tuple(words)
+                    else:
+                        data = ' '.join(words)
                     m.put(data)
     except KeyboardInterrupt:
         print('Interrupted -- continue with data read so far')
@@ -86,16 +93,19 @@ def test():
         print('No valid input files')
         return
     if debug: print('done.')
+
     if debug > 1:
         for key in m.trans.keys():
             if key is None or len(key) < histsize:
                 print(repr(key), m.trans[key])
         if histsize == 0: print(repr(''), m.trans[''])
         print()
-    while 1:
+    while True:
         data = m.get()
-        if do_words: words = data
-        else: words = string.split(data)
+        if do_words:
+            words = data
+        else:
+            words = data.split()
         n = 0
         limit = 72
         for w in words:
@@ -103,15 +113,9 @@ def test():
                 print()
                 n = 0
             print(w, end=' ')
-            n = n + len(w) + 1
+            n += len(w) + 1
         print()
         print()
 
-def tuple(list):
-    if len(list) == 0: return ()
-    if len(list) == 1: return (list[0],)
-    i = len(list)//2
-    return tuple(list[:i]) + tuple(list[i:])
-
 if __name__ == "__main__":
     test()