Selecting rows from a Dataframe based on values in multiple columns in pandas

Question

This question is very related to another, and I\'ll even use the example from the very helpful accepted solution on that question. Here\'s the example from the acce

Answer 1

You can do this with tiny altering in your code:

print(df[df['A'] == 'foo'][df['B'] == 'one'])

Output:

     A    B  C   D
0  foo  one  0   0
6  foo  one  6  12

Answer 2

There is only a very small change needed in your code: change the and with & (and add parentheses for correct ordering of comparisons):

In [104]: df.loc[(df['A'] == 'foo') & (df['B'] == 'one')]
Out[104]:
     A    B  C   D
0  foo  one  0   0
6  foo  one  6  12

The reason you have to use & is that this will do the comparison element-wise on arrays, while and expect to compare two expressions that evaluate to True or False.
Similarly, when you want the or comparison, you can use | in this case.