在 pandas.Dataframe 中查找 NaN

Question

This is my code to check if a certain cell in my Dataframe is empty. Bfore there is a for loop to iterate over the rows. the counter is i

if change.isna(change.iloc[i,3]):
         continue

Can't figure out why I receive the

**TypeError**: isna() takes 1 positional argument but 2 were given

Because I just pass one argument.... Or am I wrong?

Answer 1

The positional argument isna takes is self , because you're calling the method of pd.Dataframe ( change.isna() ). You're passing one argument, but that's the second argument to the function, hence the error.

Take a look at pd.Dataframe.isna 's documentation : there is only self specified as argument. This is, because isna actually returns a boolean array where for each element in the dataframe it tells you whether it's a valid value or NA.

if change.iloc[i].isna()[3]:
  ....

Alternatively, use the function pandas.isna() , which takes exactly one object as argument:

if pd.isna(change.iloc[i,3]):
  ....