<h2>使用<a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.sort_values.html" rel="nofollow noreferrer">^{<cd2>}</a>结果的<a href="https://docs.python.org/3/tutorial/introduction.html#lists" rel="nofollow noreferrer">^{<cd1>}</a>切片</h2>
<p>在<a href="https://stackoverflow.com/a/24989227/2087463">descending mode</a>中使用<a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.sort_values.html" rel="nofollow noreferrer">^{<cd2>}</a>,然后使用<a href="https://docs.python.org/3/tutorial/introduction.html#lists" rel="nofollow noreferrer">first ^{<cd4>} results in a slice</a>,然后使用{a6}来保留<a href="https://en.wikipedia.org/wiki/Monotonic_function" rel="nofollow noreferrer">monotonically increasing</a>。在</p>
<pre><code>import pandas as pd
import cStringIO
df = pd.read_table(cStringIO.StringIO('''
date name value
2016-05-01 kelly 20
2016-05-05 john 12
2016-05-05 sarah 25
2016-05-05 george 3
2016-05-05 tom 40
2016-05-07 kara 24
2016-05-07 jane 90
2016-05-07 sally 39
2016-05-07 sam 28
'''), sep=' *', index_col=0, engine='python')
print 'Original DataFrame:'
print df
print
df_top3 = df.sort_values('value', ascending=False)[:3].sort_index()
print 'Top 3 Largest value DataFrame:'
print df_top3
print
</code></pre>
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^{pr2}$