Changes between Version 9 and Version 10 of HelperFunctions

Timestamp:

Sep 26, 2006, 5:48:24 PM (17 years ago)

Author:

Arnar

Comment:

Removed counting functions in favor of the general countoccurrences

HelperFunctions

@@ -209 +209 @@
 }}}
 
-== countoccurrences() / countdistinct() ==
-
-Written by Arnar Birgisson and shared on the IrcChannel.
-
-{{{
-#!python
-def countoccurrences(numbers, minlength=0):
-    """Takes a list of integers, in the range of 0..n and returns a list of integers
-    where i-th item is the number of times i appears in the input list.
-    
-    If minlength is specified and n+1 < minlength, the returned list is
-    right-padded with zeroes to make it contain minlength items.
-    
-    Examples:
-    >>> countoccurrences([0,3,1,2,1,1,3,5])
-    [1,3,1,2,0,1]
-    >>> countoccurrences([0,3,1,2,1,1,3,5], 10)
-    [1,3,1,2,0,1,0,0,0,0]
-    """
-    # TODO come up with a better name
-    counts = [0] * max(max(numbers)+1, minlength)
-    for x in numbers:
-        counts[x] += 1
-    return counts
-}}}
-
-=== Example usage ===
-
-{{{
-#!xml
-<py:with vars="counts = countoccurrences([p.status.value for p in subdir.job.pages], 3)">
-    <td><span style="color: #e18f01;">${counts[0]}</span></td>
-    <td><span style="color: #249f0b;">${counts[1]}</span></td>
-    <td><span style="color: #ae0a0a;">${counts[2]}</span></td>
-</py:with>
-}}}
-
-=== Similar version with a dict, counts any hashable types ===
-
-The previous function can only count occurrences of numbers.
-This counts occurrences of any hashable types and returns a dict instead of a list.
-{{{
-#!python
-def countitemoccurrences(items, requireditems=[]):
-    """Takes a list of hashable items and returns a dict whose keys are those
-    items and the values are the counts of how many times each item appers in the list.
-    
-    If the list requireditems is specified it's values are guaranteed to be keys
-    in the resulting dict, even if they don't appear in items in which case the count will be 0
-    
-    Examples:
-    >>> counttypes('blue green green'.split(), 'blue red green'.split())
-    {'blue': 1, 'green': 2, 'red': 0}
-    """
-    counts = dict()
-    for i in requireditems:
-        counts[i] = 0
-    for i in items:
-        counts[i] = counts.get(i, 0) + 1
-    return counts
-}}}
-
-=== Generic version based on `itertools.groupby` ===
+=== countoccurrences ===
+
+Written by [http://www.cmlenz.net/ Christopher Lenz] with a small bugfix by Arnar.
 
 {{{
@@ -300 +240 @@
     {'buzz': 2}
     """
-    return dict([(g, 0) for g in groups] +
-                [(g, len(list(l))) for g, l in groupby(iterable, key=key)])
+    d = dict([(g, 0) for g in groups])
+    for g, l in groupby(iterable, key=key):
+        d[g] = len(list(l)) + d.get(g, 0)
+    return d
 }}}