def reverse_index_1d(state):
    """The inverse of index_1d. From an row number in the transition matrix return the row and column in the grid world.

    Parameters
    ----------
    state : int
        An integer representing the row in the transition matrix.

    Returns
    -------
    row : int
        The row in the grid world.
    column : int
        The column in the grid world.\
    """
    max_cols = 9
    row = state / max_cols
    col = state % max_cols
    return row, col