擅长:python、mysql、java
<p>只需沿着<code>axis=1</code>使用<code>apply</code>函数,并将<code>pattern</code>参数作为附加参数传递给函数。在</p>
<pre><code>In [3]: def func(row, pattern):
referrer = np.nan
for key in row.index:
if row[key] == pattern:
referrer = key
return referrer
df['last_referred'] = df.apply(func, pattern='referred', axis=1)
df
Out[3]: name action_1 action_2 action_3 last_referred
0 bill referred referred None action_2
1 bob introduced referred referred action_3
2 mary introduced NaN
3 june introduced referred action_2
4 dale referred action_1
5 donna introduced NaN
</code></pre>