擅长:python、mysql、java
<p>可以使用<code>pd.DateOffset</code>从每个值中减去0.5秒:</p>
<pre><code>df.index - pd.DateOffset(seconds=0.5)
print(df)
DatetimeIndex(['2018-01-22 21:38:59.500000', '2018-01-22 21:39:00.500000',
'2018-01-22 21:39:02.500000', '2018-01-22 21:39:05.500000',
'2018-01-22 21:39:06.500000', '2018-01-22 21:39:07.500000',
'2018-01-22 21:39:08.500000', '2018-01-22 21:39:09.500000',
'2018-01-22 21:39:10.500000', '2018-01-22 21:39:11.500000'],
dtype='datetime64[ns]', name=0, freq=None)
</code></pre>