Pandas slicing/selecting with multiple conditions with or statement

Question

When I select by chaining different conditions with \"AND\" the selection works fine. When I select by chaining conditions with \"OR\" the selection throws an error.

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Answer 1

The important thing to note is that & is not identical to and they are different things so the "or" equivalent to to & is |

Normally both & and | are bitwise logical operators rather than the python "logical" operators.

In pandas these operators are overloaded for Series operation.

In [1]: import pandas as pd

In [2]: import numpy as np

In [3]: df = pd.DataFrame([[1,4,3],[2,3,5],[4,5,6],[3,2,5]], columns=['a', 'b',
   ...:  'c'])

In [4]: df
Out[4]:
   a  b  c
0  1  4  3
1  2  3  5
2  4  5  6
3  3  2  5

In [5]: df.loc[(df.a != 1) & (df.b < 5)]
Out[5]:
   a  b  c
1  2  3  5
3  3  2  5

In [6]: df.loc[(df.a != 1) | (df.b < 5)]
Out[6]:
   a  b  c
0  1  4  3
1  2  3  5
2  4  5  6
3  3  2  5