pandas Boolean indexing of dataframes Accessing a DataFrame with a boolean index
Example
This will be our example data frame:
df = pd.DataFrame({"color": ['red', 'blue', 'red', 'blue']},
index=[True, False, True, False])
color
True red
False blue
True red
False blue
Accessing with .loc
df.loc[True]
color
True red
True red
Accessing with .iloc
df.iloc[True]
>> TypeError
df.iloc[1]
color blue
dtype: object
Important to note is that older pandas versions did not distinguish between boolean and integer input, thus
.iloc[True]would return the same as.iloc[1]
Accessing with .ix
df.ix[True]
color
True red
True red
df.ix[1]
color blue
dtype: object
As you can see, .ix has two behaviors. This is very bad practice in code and thus it should be avoided. Please use .iloc or .loc to be more explicit.
