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<H2><A NAME=
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The following examples show common uses for each tool and
demonstrate ways they can be combined.
<div class=
"verbatim"><pre>
>>> amounts = [
120.15,
764.05,
823.14]
>>> for checknum, amount in izip(count(
1200), amounts):
... print 'Check %d is for $%
.2f' % (checknum, amount)
Check
1200 is for $
120.15
Check
1201 is for $
764.05
Check
1202 is for $
823.14
>>> import operator
>>> for cube in imap(operator.pow, xrange(
1,
5), repeat(
3)):
>>> reportlines = ['EuroPython', 'Roster', '', 'alex', '', 'laura',
'', 'martin', '', 'walter', '', 'mark']
>>> for name in islice(reportlines,
3, None,
2):
# Show a dictionary sorted and grouped by value
>>> from operator import itemgetter
>>> d = dict(a=
1, b=
2, c=
1, d=
2, e=
1, f=
2, g=
3)
>>> di = sorted(d.iteritems(), key=itemgetter(
1))
>>> for k, g in groupby(di, key=itemgetter(
1)):
... print k, map(itemgetter(
0), g)
# Find runs of consecutive numbers using groupby. The key to the solution
# is differencing with a range so that consecutive numbers all appear in
>>> data = [
1,
4,
5,
6,
10,
15,
16,
17,
18,
22,
25,
26,
27,
28]
>>> for k, g in groupby(enumerate(data), lambda (i,x):i-x):
... print map(operator.itemgetter(
1), g)
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<span class=
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2.4.2, documentation updated on
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2005.
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