Boolean column comparison in Python / Pandas

Question

I am trying to take 2 columns in Pandas that contain Boolean values and create a third column that is the OR of these Boolean values.

For example, my dataframe currently contains A and B, and I want to create C.

A B C
True True True
False False False
True False True
False True True

My code:

df['C']=df['A'] or df['B']

I have tried to change the structure of the statement several ways but end up with the same error message:

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

Answer 1

Use np.logical_or:

In [436]:
df['C'] = np.logical_or(df['A'], df['B'])
df
Out[436]:
       A      B      C
0   True   True   True
1  False  False  False
2   True  False   True
3  False   True   True

You can't use or operator here as it becomes ambiguous comparing arrays.

or use the bitwise | operator for array comparisons:

In [445]:
df['C'] = df['A'] | df['B']
df

Out[445]:
       A      B      C
0   True   True   True
1  False  False  False
2   True  False   True
3  False   True   True