A.2 The magic 8-ball output is wrong

Codebook
1

I am trying to follow the material but I got an error :

def oracle_matrix(combo):
    """Return the oracle matrix for a secret combination.
    
    Args:
        combo (list[int]): A list of bits
        representing a secret combination.
         
    Returns: 
        array[float]: The matrix
        representation of the oracle.
    """
    index = np.array(np.ravel_multi_index(combo, [2]*len(combo))) 
    # Index of solution
    my_array = np.identity(2**len(combo))
    # Create the identity matrix

    ##################
    # YOUR CODE HERE #
    ##################

    # MODIFY DIAGONAL ENTRY CORRESPONDING TO SOLUTION INDEX
    my_array[index-1][index-1] = -1  # modifying the index here by -1 gives error: Incorrect: your matrix doesn't look quite right.

    return my_array

any idea

2

It was here;

my_array[index-1][index-1] = -1

should be replaced by:

my_array[index , index] = -1
3

I’m glad you solved your error @Afrah !