def split_data(data):
    """
    Split the matrix in 2 matrices one for sense the other for antisense.

    :param data: the coverage data to split
    :type data: a 2 dimension :class:`pandas.DataFrame` object
    :return: two matrix
    :rtype: tuple of two :class:`pandas.DataFrame` object (sense pandas.DataFrame, antisense pandas.DataFrame)
    """
    grp = data.groupby(by=['sense'])
    return grp.get_group('S').copy(), grp.get_group('AS').copy()
