计算整个熊猫数据框中某个字符串的出现次数

Question

I have following dataframe in pandas我在熊猫中有以下数据框

 C1      C2       C3
 10      a        b
 10      a        b
 ?       c        c
 ?       ?        b
 10      a        b
 10      ?        ?

I want to count the occurrences of ?我想计算? in all the columns在所有列中

My desired output is column wise sum of occurrences我想要的输出是按列出现的总和

Answer 1

Use:用：

m=df.eq('?').sum()
pd.DataFrame([m.values],columns=m.index)

   C1  C2  C3
0   2   2   1

Or better :或更好：

df.eq('?').sum().to_frame().T #thanks @user3483203

C1  C2  C3
0   2   2   1