Python 获取跨列的值计数-Pandas DataFrame
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Get count of values across columns-Pandas DataFrame
提问by Nilani Algiriyage
I have a Pandas DataFrame like following:
我有一个 Pandas DataFrame，如下所示：
A B C
0 192.168.2.85 192.168.2.85 124.43.113.22
1 192.248.8.183 192.248.8.183 192.168.2.85
2 192.168.2.161 NaN 192.248.8.183
3 66.249.74.52 NaN 192.168.2.161
4 NaN NaN 66.249.74.52
I want to get the count of a certain values across columns. So my expected output is something like:
我想跨列获取某个值的计数。所以我的预期输出是这样的：
IP Count
192.168.2.85 3 #Since this value is there in all coulmns
192.248.8.183 3
192.168.2.161 2
66.249.74.52 2
124.43.113.22 1
I know how to this across rows, but doing this for columns is bit strange?Help me to solve this? Thanks.
我知道如何跨行执行此操作，但是对列执行此操作有点奇怪？帮我解决这个问题吗？谢谢。
采纳答案by waitingkuo
stackit first and then use value_counts:
首先堆叠它，然后使用value_counts：
In [14]: df.stack().value_counts()
Out[14]:
192.248.8.183 3
192.168.2.85 3
66.249.74.52 2
192.168.2.161 2
124.43.113.22 1
dtype: int64
回答by Vamshi G
df['Counts'] = df[['col1','col2','col3']].groupby(['col1','col2','col3']).transform('count')
