Shift NaNs to the end of their respective rows

Question

I have a DataFrame like :

     0    1    2
0  0.0  1.0  2.0
1  NaN  1.0  2.0
2  NaN  NaN  2.0

---

What I want to get is

Answer 1

Your best easiest option is to use sorted on df.apply/df.transform and sort by nullity.

df = df.apply(lambda x: sorted(x, key=pd.isnull), 1)
df
     0    1    2
0  0.0  1.0  2.0
1  1.0  2.0  NaN
2  2.0  NaN  NaN

You may also pass np.isnan to the key argument.