擅长:python、mysql、java
<p>您可以先将数据帧重塑为“堆叠”记录,然后使用<code>value_counts</code>函数。在</p>
<pre><code>import pandas as pd
# your data
# ===================
print(df)
Out[269]:
N Shelf1 Shelf2 Shelf3
0 Case1 Python PHP Python
1 Case2 Rails R PHP
2 Case3 PHP Python Python
# processing
# ======================================
# make column 'N' as index, stack, then value_counts
df.set_index('N').stack().value_counts()
Out[270]:
Python 4
PHP 3
Rails 1
R 1
dtype: int64
</code></pre>