How to select cells greater than a value in a multi-index Pandas dataframe?

Question

Try 1:

df[ df > 1.0 ] : this returned all cells in NAN.

Try2:

df.loc[ df > 1.0 ] : this returned KeyError: 0

df[df['A']> 1.0] : this works - But I want to apply the filter condition to all columns.

Answer 1

If what you are trying to do is to select only rows where any one column meets the condition , you can use DataFrame.any() along with axis=1 (to do row-wise grouping) . Example -

In [3]: df
Out[3]:
   A  B  C
0  1  2  3
1  3  4  5
2  3  1  4

In [6]: df[(df <= 2).any(axis=1)]
Out[6]:
   A  B  C
0  1  2  3
2  3  1  4

Alternatively, if you are trying for filtering rows where all columns meet the condition , use .all() inplace of .any() . Example of all -

In [8]: df = pd.DataFrame([[1,2,3],[3,4,5],[3,1,4],[1,2,1]],columns=['A','B','C'])

In [9]: df
Out[9]:
   A  B  C
0  1  2  3
1  3  4  5
2  3  1  4
3  1  2  1

In [11]: df[(df <= 2).all(axis=1)]
Out[11]:
   A  B  C
3  1  2  1