def create_rating_dict(set_df):
    """Creates a rating dictionary for efficient rating updates. 

    :param set_df: Dataframe for a single set.
    
    :return: Returns a rating dictionary. The keys in the dictionary are 
             cardnames (strings). The value corresponding to each key is a 
             list of length two. The first element of the list is the 'Color
             Vector' for the card. The second element is the rating for the 
             card. The rating is allowed to change during optimization.
    """
    rating_dict = {}
    for index, row in set_df.iterrows():
        rating_dict[row["Name"]] = [row["Color Vector"], row["Rating"]]
    return rating_dict