def r_to_depth(x, interval):
    """Computes rainfall depth (mm) from rainfall intensity (mm/h)

    Parameters
    ----------
    x : float,
        float or array of float
        rainfall intensity in mm/h
    interval : number
        time interval (s) the values of `x` represent

    Returns
    -------
    output : float
        float or array of float
        rainfall depth (mm)

    """
    return x * interval / 3600.0
