First non-null value per row from a list of Pandas columns

Question

If I\'ve got a DataFrame in pandas which looks something like:

    A   B   C
0   1 NaN   2
1 NaN   3 NaN
2 NaN   4   5
3 NaN NaN NaN

How ca

Answer 1

Fill the nans from the left with fillna, then get the leftmost column:

df.fillna(method='bfill', axis=1).iloc[:, 0]