擅长:python、mysql、java
<p>这是一种方法。在</p>
<pre><code># convert to datetime
df['timestamp'] = pd.to_datetime(df['timestamp'])
# normalize, count values, convert to dataframe
res = df['timestamp'].dt.normalize()\
.value_counts()\
.to_frame().reset_index()
# rename columns
res.columns = ['timestamp', 'count']
</code></pre>
<p>结果:</p>
^{pr2}$