pandas dataframe drop columns by number of nan

Question

I have a dataframe with some columns containing nan. I\'d like to drop those columns with certain number of nan. For example, in the following code, I\'d like to drop any co

Answer 1

Here is a possible solution:

s = dff.isnull().apply(sum, axis=0) # count the number of nan in each column
print s
   A    1 
   B    1
   C    3
   dtype: int64

for col in dff: 
   if s[col] >= 2:  
       del dff[col]

Or

for c in dff:
    if sum(dff[c].isnull()) >= 2:
        dff.drop(c, axis=1, inplace=True)