cleanup

Author: ahms5

imkar/scattering/diffuse.py

@@ -90,91 +90,3 @@ def maximum_baseplate_scattering_coefficient(N: int = 1) -> pf.FrequencyData:
         frequencies=np.array(frequencies)/N,
         comment="Maximum scattering coefficient of the baseplate",
     )
-
-def calculation(
-        reverberation_times, speed_of_sound,
-        air_attenuation_coefficient,
-        volume, surface_sample) -> tuple:
-    """
-    Calculate the diffuse scattering coefficient after ISO 17497-1:2004.
-
-    Measurement conditions for the four different reverberation times
-    and the corresponding speed of sound and air attenuation
-    coefficients based on Table 2 in ISO 17497-1:2004 [#]_.
-
-    +------------------------+-------------+--------------+
-    | measurement condition  | test sample |  turntable   |
-    +------------------------+-------------+--------------+
-    |           1            | not present | not rotating |
-    +------------------------+-------------+--------------+
-    |           2            |   present   | not rotating |
-    +------------------------+-------------+--------------+
-    |           3            | not present |   rotating   |
-    +------------------------+-------------+--------------+
-    |           4            |   present   |   rotating   |
-    +------------------------+-------------+--------------+
-
-    Parameters
-    ----------
-    reverberation_times : pf.FrequencyData
-        The reverberation times in seconds of the measurement conditions of
-        cshape (..., 4).
-    speed_of_sound : np.ndarray
-        is the speed of sound in air, in metres per second (m/s),
-        during the measurement of each measurement conditions of
-        shape (..., 4).
-    air_attenuation_coefficient : pf.FrequencyData
-        the energy attenuation coefficient of air, in reciprocal metres
-        (:math:`m^-1`), calculated according to ISO 9613-1,
-        using the temperature and relative humidity during the measurement
-        of each measurement conditions of cshape (..., 4).
-    volume : float
-        volume of the reverberation room, in cubic metres (:math:`m^3`).
-    surface_sample : float
-        is the area of the test sample, in square metres (:math:`m^2`).
-
-    Returns
-    -------
-    scattering : pf.FrequencyData
-        The random-incidence scattering coefficient.
-    s_base : pf.FrequencyData
-        The base plate scattering coefficient.
-    alpha_s : pf.FrequencyData
-        The random-incidence absorption coefficient.
-    alpha_spec : pf.FrequencyData
-        The random-incidence specular absorption coefficient.
-
-    References
-    ----------
-    .. [#] ISO 17497-1:2004, Sound-scattering properties of surfaces. Part 1:
-           Measurement of the random-incidence scattering coefficient in a
-           reverberation room. Geneva, Switzerland: International Organization
-           for Standards, 2004.
-    """
-    T_1 = reverberation_times[..., 0]
-    T_2 = reverberation_times[..., 1]
-    T_3 = reverberation_times[..., 2]
-    T_4 = reverberation_times[..., 3]
-    c_1 = speed_of_sound[..., 0]
-    c_2 = speed_of_sound[..., 1]
-    c_3 = speed_of_sound[..., 2]
-    c_4 = speed_of_sound[..., 3]
-    m_1 = air_attenuation_coefficient[..., 0]
-    m_2 = air_attenuation_coefficient[..., 1]
-    m_3 = air_attenuation_coefficient[..., 2]
-    m_4 = air_attenuation_coefficient[..., 3]
-    V = volume
-    S = surface_sample
-
-    # random incident absorption coefficient
-    alpha_s = 55.3 * V/S * (1/(c_2*T_2) - 1/(c_1*T_1)) - 4*V/S * (m_2-m_1)
-
-    # specular absorption coefficient
-    alpha_spec = 55.3 * V/S * (1/(c_4*T_4) - 1/(c_3*T_3)) - 4*V/S * (m_4-m_3)
-
-    # calculate scattering coefficient
-    scattering = (alpha_spec - alpha_s) / (1 - alpha_s)
-
-    s_base = 55.3*V/S*(1/(c_3*T_3) - 1/(c_1*T_1)) - 4*V/S*(m_3-m_1)
-
-    return scattering, s_base, alpha_s, alpha_spec