擅长:python、mysql、java
<p>可以使用Counter()计算colA中每个值的频率,然后创建一个函数来生成colB的值列表</p>
<pre><code>from collections import Counter
def count_value(colA):
new_col = []
colA = df[colA].tolist()
freq_table = Counter(colA) # count the frequency of each value
for value in colA:
new_col.append('00' + str(freq_table[value]))
return new_col
df['colB'] = count_value(df['colA'])
</code></pre>