擅长:python、mysql、java
<p>解决了这个问题</p>
<pre class="lang-python prettyprint-override"><code>def node_counter(id_x, parent_ID):
counter = 0
for child in parent_ID:
if child == id_x:
counter += 1
return counter
df['Amount'] = df.apply(lambda x: node_counter(x['id_x'], df['parentId']), axis=1)
df
| parentId | id_x | Amount |
| | | |
| 071cb2c2-d1be-4154-b6c7-a29728357ef3 | a061e7d7-95d2-4812-87c1-24ec24fc2dd2 | 1 |
| a061e7d7-95d2-4812-87c1-24ec24fc2dd2 | d2b62e36-b243-43ac-8e45-ed3f269d50b2 | 0 |
| None | 071cb2c2-d1be-4154-b6c7-a29728357ef3 | 2 |
| 071cb2c2-d1be-4154-b6c7-a29728357ef3 | a0e97b37-b9a1-4304-9769-b8c48cd9f184 | 0 |
</code></pre>