擅长:python、mysql、java
<p>与<a href="https://stackoverflow.com/users/4542359/anton-protopopov">Anton's</a>类似,味道略有不同:</p>
<pre><code>df['date'] = pd.to_datetime(df['date'])
def Age(df):
df.reset_index(drop=True, inplace=True)
df['age'] = [x-df.date[0] for x in df.date]
return df
df = df.groupby('id').apply(Age)
</code></pre>