Exemplo n.º 1
0
def get_DNVGL_Hs_Tz():
    """
    Get DNVGL significant wave height and wave period model.
    
    Get the descriptions necessary to create th significant wave height 
    and wave period model as defined in DNVGL [1]_ in section 3.6.3.
    
    Returns
    -------
    dist_descriptions : list of dict
        List of dictionaries containing the dist descriptions for each dimension.
        Can be used to create a GlobalHierarchicalModel.
    fit_descriptions : None
        Default fit is used so None is returned. 
        Can be passed to fit function of GlobalHierarchicalModel.
    semantics : dict
        Dictionary with a semantic description of the model.
        Can be passed to plot functions.
    
    References
    ----------
    .. [1] DNV GL (2017). Recommended practice DNVGL-RP-C205: Environmental 
        conditions and environmental loads.
        
    """
    # TODO docstrings with links to literature
    # DNVGL 3.6.3
    def _power3(x, a, b, c):
        return a + b * x ** c

    def _exp3(x, a, b, c):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]

    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    dist_description_hs = {
        "distribution": WeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=0.5),
    }

    dist_description_tz = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {"mu": power3, "sigma": exp3},
    }

    dist_descriptions = [dist_description_hs, dist_description_tz]

    fit_descriptions = None

    semantics = {
        "names": ["Significant wave height", "Zero-crossing wave period"],
        "symbols": ["H_s", "T_z"],
        "units": ["m", "s"],
    }

    return dist_descriptions, fit_descriptions, semantics
Exemplo n.º 2
0
def test_HDC(reference_coordinates_HDC):
    def _power3(x, a=0.1000, b=1.489, c=0.1901):
        return a + b * x**c

    # A 3-parameter exponential function (a dependence function).
    def _exp3(x, a=0.0400, b=0.1748, c=-0.2243):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]
    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    dist_description_0 = {
        "distribution": WeibullDistribution(alpha=2.776,
                                            beta=1.471,
                                            gamma=0.8888),
    }
    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": power3,
            "sigma": exp3
        },
    }
    ghm = GlobalHierarchicalModel([dist_description_0, dist_description_1])

    alpha = calculate_alpha(3, 50)
    limits = [(0, 20), (0, 18)]
    deltas = [0.1, 0.1]
    my_contour = HighestDensityContour(ghm, alpha, limits, deltas)

    my_coordinates = my_contour.coordinates

    np.testing.assert_allclose(my_coordinates, reference_coordinates_HDC)
Exemplo n.º 3
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def seastate_model():
    """
    This joint distribution model described by Vanem and Bitner-Gregersen (2012)
    is widely used in academia. Here, we use it for evaluation. 
    DOI: 10.1016/j.apor.2012.05.006
    """
    def _power3(x, a=0.1000, b=1.489, c=0.1901):
        return a + b * x**c

    # A 3-parameter exponential function (a dependence function).
    def _exp3(x, a=0.0400, b=0.1748, c=-0.2243):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]
    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    dist_description_0 = {
        "distribution": WeibullDistribution(alpha=2.776,
                                            beta=1.471,
                                            gamma=0.8888),
    }
    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": power3,
            "sigma": exp3
        },
    }
    model = GlobalHierarchicalModel([dist_description_0, dist_description_1])

    return model
Exemplo n.º 4
0
def get_DNVGL_Hs_U():
    """
    Get DNVGL significant wave height and wind speed model.
    
    Get the descriptions necessary to create the significant wave height 
    and wind speed model as defined in DNVGL [1]_ in section 3.6.4.
    
    Returns
    -------
    dist_descriptions : list of dict
        List of dictionaries containing the dist descriptions for each dimension.
        Can be used to create a GlobalHierarchicalModel.
    fit_descriptions : None
        Default fit is used so None is returned. 
        Can be passed to fit function of GlobalHierarchicalModel.
    semantics : dict
        Dictionary with a semantic description of the model.
        Can be passed to plot functions.
        
    References
    ----------
    .. [1] DNV GL (2017). Recommended practice DNVGL-RP-C205: Environmental 
        conditions and environmental loads.
    """
    def _power3(x, a, b, c):
        return a + b * x**c

    bounds = [(0, None), (0, None), (None, None)]

    alpha_dep = DependenceFunction(_power3, bounds=bounds)
    beta_dep = DependenceFunction(_power3, bounds=bounds)

    dist_description_hs = {
        "distribution": WeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=0.5, min_n_points=20),
    }

    dist_description_u = {
        "distribution": WeibullDistribution(f_gamma=0),
        "conditional_on": 0,
        "parameters": {
            "alpha": alpha_dep,
            "beta": beta_dep,
        },
    }

    dist_descriptions = [dist_description_hs, dist_description_u]

    fit_descriptions = None

    semantics = {
        "names": ["Significant wave height", "Mean wind speed"],
        "symbols": ["H_s", "U"],
        "units": ["m", "m s$^{-1}$"],
    }

    return dist_descriptions, fit_descriptions, semantics
Exemplo n.º 5
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def test_DirectSamplingContour(reference_data_DSContour):

    sample = reference_data_DSContour["sample"]
    ref_coordinates = reference_data_DSContour["ref_coordinates"]

    def _power3(x, a=0.1000, b=1.489, c=0.1901):
        return a + b * x**c

    # A 3-parameter exponential function (a dependence function).
    def _exp3(x, a=0.0400, b=0.1748, c=-0.2243):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]
    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    dist_description_0 = {
        "distribution": WeibullDistribution(alpha=2.776,
                                            beta=1.471,
                                            gamma=0.8888),
    }
    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": power3,
            "sigma": exp3
        },
    }
    ghm = GlobalHierarchicalModel([dist_description_0, dist_description_1])

    alpha = calculate_alpha(3, 50)
    my_ds_contour = DirectSamplingContour(ghm, alpha, sample=sample)

    my_coordinates = my_ds_contour.coordinates

    np.testing.assert_allclose(my_coordinates, ref_coordinates)
Exemplo n.º 6
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def test_ISORM(reference_coordinates_ISORM):

    # Logarithmic square function.
    def _lnsquare2(x, a=3.62, b=5.77):
        return np.log(a + b * np.sqrt(x / 9.81))

    # 3-parameter function that asymptotically decreases (a dependence function).
    def _asymdecrease3(x, a=0, b=0.324, c=0.404):
        return a + b / (1 + c * x)

    lnsquare2 = DependenceFunction(_lnsquare2)
    asymdecrease3 = DependenceFunction(_asymdecrease3)

    dist_description_0 = {
        "distribution":
        ExponentiatedWeibullDistribution(alpha=0.207, beta=0.684, delta=7.79),
    }

    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": lnsquare2,
            "sigma": asymdecrease3
        },
    }

    ghm = GlobalHierarchicalModel([dist_description_0, dist_description_1])

    state_duration = 3
    return_period = 20
    alpha = calculate_alpha(state_duration, return_period)
    my_isorm = ISORMContour(ghm, alpha)

    my_coordinates = my_isorm.coordinates

    np.testing.assert_allclose(my_coordinates, reference_coordinates_ISORM)
Exemplo n.º 7
0
def get_OMAE2020_Hs_Tz():
    """
    Get OMAE2020 significant wave height and wave period model.
    
    Get the descriptions necessary to create the significant wave height 
    and wave period model as described by Haselsteiner et al. [1]_. 
    
    Returns
    -------
    dist_descriptions : list of dict
        List of dictionaries containing the dist descriptions for each dimension.
        Can be used to create a GlobalHierarchicalModel.
    fit_descriptions : list of dict
        List of dictionaries containing the fit description for each dimension.
        Can be passed to fit function of GlobalHierarchicalModel.
    semantics : dict
        Dictionary with a semantic description of the model.
        Can be passed to plot functions.
        
    References
    ----------
    .. [1] Haselsteiner, A.F.; Sander, A.; Ohlendorf, J.H.; Thoben, K.D. (2020)
        Global hierarchical models for wind and wave contours: Physical
        interpretations of the dependence functions. OMAE 2020, Fort Lauderdale,
        USA. Proceedings of the 39th International Conference on Ocean, 
        Offshore and Arctic Engineering.
    """

    def _asymdecrease3(x, a, b, c):
        return a + b / (1 + c * x)

    def _lnsquare2(x, a, b, c):
        return np.log(a + b * np.sqrt(np.divide(x, 9.81)))

    bounds = [(0, None), (0, None), (None, None)]

    sigma_dep = DependenceFunction(_asymdecrease3, bounds=bounds)
    mu_dep = DependenceFunction(_lnsquare2, bounds=bounds)

    dist_description_hs = {
        "distribution": ExponentiatedWeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=0.5, min_n_points=50),
    }

    dist_description_tz = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {"sigma": sigma_dep, "mu": mu_dep,},
    }

    dist_descriptions = [dist_description_hs, dist_description_tz]

    fit_description_hs = {"method": "wlsq", "weights": "quadratic"}
    fit_descriptions = [fit_description_hs, None]

    semantics = {
        "names": ["Significant wave height", "Zero-crossing wave period"],
        "symbols": ["H_s", "T_z"],
        "units": ["m", "s"],
    }

    return dist_descriptions, fit_descriptions, semantics
)


# %%
# OMEA2019 A
# A 3-parameter power function (a dependence function).
def _power3(x, a=1.47, b=0.214, c=0.641):
    return a + b * x**c


# A 3-parameter exponential function (a dependence function).
def _exp3(x, a=0.0, b=0.308, c=-0.250):
    return a + b * np.exp(c * x)


power3 = DependenceFunction(_power3)
exp3 = DependenceFunction(_exp3)

dist_description_0 = {
    "distribution": WeibullDistribution(alpha=0.944, beta=1.48, gamma=0.0981),
}

dist_description_1 = {
    "distribution": LogNormalDistribution(),
    "conditional_on": 0,
    "parameters": {
        "mu": power3,
        "sigma": exp3
    },
}
Exemplo n.º 9
0
# _logistics4 = lambda x, a, b, c=-1, d=1 : a + b / (1 + np.exp(c * (x - d)))


# A 3-parameter function designed for the scale parameter (alpha) of an
# exponentiated Weibull distribution with shape2=5 (see 'Global hierarchical
# models for wind and wave contours').
def _alpha3(x, a, b, c, d_of_x):
    return (a + b * x**c) / 2.0445**(1 / d_of_x(x))


logistics_bounds = [(0, None), (0, None), (None, 0), (0, None)]

alpha_bounds = [(0, None), (0, None), (None, None)]

beta_dep = DependenceFunction(_logistics4,
                              logistics_bounds,
                              weights=lambda x, y: y)
alpha_dep = DependenceFunction(_alpha3,
                               alpha_bounds,
                               d_of_x=beta_dep,
                               weights=lambda x, y: y)

dist_description_vs = {
    "distribution": ExponentiatedWeibullDistribution(),
    "intervals": WidthOfIntervalSlicer(2, min_n_points=50),
}

dist_description_hs = {
    "distribution": ExponentiatedWeibullDistribution(f_delta=5),
    "conditional_on": 0,
    "parameters": {
Exemplo n.º 10
0
def test_v_hs_hd_contour():
    """
    Use a wind speed - wave height dataset, fit the joint 
    distribution that was proposed by Haselsteiner et al. (2020)
    and compute a highest density contour. This test reproduces
    the results presented in Haselestiner et al. (2020). The
    coorindates are availble at https://github.com/ec-benchmark-organizers/
    ec-benchmark/blob/master/results/exercise-1/contribution-4/haselsteiner_
    andreas_dataset_d_50.txt

    Such a work flow is for example typical when generationg 
    a 50-year contour for DLC 1.6 in the offshore wind standard
    IEC 61400-3-1.

    Haselsteiner, A. F., Sander, A., Ohlendorf, J.-H., & Thoben, K.-D. (2020). 
    Global hierarchical models for wind and wave contours: Physical 
    interpretations of the dependence functions. Proc. 39th International 
    Conference on Ocean, Offshore and Arctic Engineering (OMAE 2020). 
    https://doi.org/10.1115/OMAE2020-18668

    International Electrotechnical Commission. (2019). Wind energy 
    generation systems - Part 3-1: Design requirements for fixed 
    offshore wind turbines (IEC 61400-3-1).
    """

    data = read_ec_benchmark_dataset("datasets/ec-benchmark_dataset_D.txt")

    def _logistics4(x, a=1, b=1, c=-1, d=1):
        return a + b / (1 + np.exp(c * (x - d)))

    def _alpha3(x, a, b, c, d_of_x):
        return (a + b * x**c) / 2.0445**(1 / d_of_x(x))

    logistics_bounds = [(0, None), (0, None), (None, 0), (0, None)]

    alpha_bounds = [(0, None), (0, None), (None, None)]

    beta_dep = DependenceFunction(_logistics4,
                                  logistics_bounds,
                                  weights=lambda x, y: y)
    alpha_dep = DependenceFunction(_alpha3,
                                   alpha_bounds,
                                   d_of_x=beta_dep,
                                   weights=lambda x, y: y)

    dist_description_v = {
        "distribution": ExponentiatedWeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=2),
    }

    dist_description_hs = {
        "distribution": ExponentiatedWeibullDistribution(f_delta=5),
        "conditional_on": 0,
        "parameters": {
            "alpha": alpha_dep,
            "beta": beta_dep,
        },
    }

    model = GlobalHierarchicalModel([dist_description_v, dist_description_hs])

    fit_description_vs = {"method": "wlsq", "weights": "quadratic"}
    fit_description_hs = {"method": "wlsq", "weights": "quadratic"}

    model.fit(data, [fit_description_vs, fit_description_hs])

    axs = plot_marginal_quantiles(model, data)
    axs = plot_dependence_functions(model)
    ax = plot_2D_isodensity(model, data)

    alpha = calculate_alpha(1, 50)
    limits = [(0, 35), (0, 20)]
    contour = HighestDensityContour(model,
                                    alpha,
                                    limits=limits,
                                    deltas=[0.2, 0.2])

    coordinates = contour.coordinates
    np.testing.assert_allclose(max(coordinates[:, 0]), 29.9, atol=0.2)
    np.testing.assert_allclose(max(coordinates[:, 1]), 15.5, atol=0.2)
    np.testing.assert_allclose(min(coordinates[:, 0]), 0, atol=0.1)
    np.testing.assert_allclose(min(coordinates[:, 1]), 0, atol=0.1)

    ax = plot_2D_contour(contour, sample=data)
Exemplo n.º 11
0
def test_hs_tz_iform_contour():
    """
    Use a sea state dataset with the variables Hs and Tz,
    fit the join distribution recommended in DNVGL-RP-C203 to 
    it and compute an IFORM contour. This tests reproduces
    the results published in Haseltseiner et al. (2019).

    Such a work flow is for example typical in ship design.

    Haselsteiner, A. F., Coe, R. G., Manuel, L., Nguyen, P. T. T., 
    Martin, N., & Eckert-Gallup, A. (2019). A benchmarking exercise 
    on estimating extreme environmental conditions: Methodology & 
    baseline results. Proc. 38th International Conference on Ocean, 
    Offshore and Arctic Engineering (OMAE 2019). 
    https://doi.org/10.1115/OMAE2019-96523
    
    DNV GL. (2017). Recommended practice DNVGL-RP-C205: 
    Environmental conditions and environmental loads.
    """

    data = read_ec_benchmark_dataset("datasets/ec-benchmark_dataset_A.txt")

    # A 3-parameter power function (a dependence function).
    def _power3(x, a, b, c):
        return a + b * x**c

    # A 3-parameter exponential function (a dependence function).
    def _exp3(x, a, b, c):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]
    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    dist_description_0 = {
        "distribution": WeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=0.5),
    }
    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": power3,
            "sigma": exp3
        },
    }
    model = GlobalHierarchicalModel([dist_description_0, dist_description_1])
    model.fit(data)

    axs = plot_marginal_quantiles(model, data)
    axs = plot_dependence_functions(model)
    ax = plot_2D_isodensity(model, data)

    alpha = calculate_alpha(1, 20)
    contour = IFORMContour(model, alpha)

    coordinates = contour.coordinates
    np.testing.assert_allclose(max(coordinates[:, 0]), 5.0, atol=0.5)
    np.testing.assert_allclose(max(coordinates[:, 1]), 16.1, atol=0.5)

    ax = plot_2D_contour(contour, sample=data)
Exemplo n.º 12
0
    ISORMContour,
)

x = np.linspace((0, 0), (10, 10), num=100)

# Logarithmic square function.
def _lnsquare2(x, a=3.62, b=5.77):
    return np.log(a + b * np.sqrt(x / 9.81))


# 3-parameter function that asymptotically decreases (a dependence function).
def _asymdecrease3(x, a=0, b=0.324, c=0.404):
    return a + b / (1 + c * x)


lnsquare2 = DependenceFunction(_lnsquare2)
asymdecrease3 = DependenceFunction(_asymdecrease3)

dist_description_0 = {
    "distribution": ExponentiatedWeibullDistribution(
        alpha=0.207, beta=0.684, delta=7.79
    ),
}

dist_description_1 = {
    "distribution": LogNormalDistribution(),
    "conditional_on": 0,
    "parameters": {"mu": lnsquare2, "sigma": asymdecrease3},
}

ghm = GlobalHierarchicalModel([dist_description_0, dist_description_1])
data = pd.read_csv("datasets/NDBC_buoy_46025.csv", sep=",")[["Hs", "T"]]


# A 3-parameter power function (a dependence function).
def _power3(x, a, b, c):
    return a + b * x**c


# A 3-parameter exponential function (a dependence function).
def _exp3(x, a, b, c):
    return a + b * np.exp(c * x)


bounds = [(0, None), (0, None), (None, None)]

power3 = DependenceFunction(_power3, bounds)
exp3 = DependenceFunction(_exp3, bounds)

dist_description_0 = {
    "distribution": WeibullDistribution(),
    "intervals": WidthOfIntervalSlicer(width=0.5),
}

dist_description_1 = {
    "distribution": LogNormalDistribution(),
    "conditional_on": 0,
    "parameters": {
        "mu": power3,
        "sigma": exp3
    },
}
def _exp3(x, a=2, b=2, c=2):
    return a + b * np.exp(c * x)


smallest_positive_float = np.nextafter(0, 1)
# 0 < a < inf
# 0 < b < inf
# exp_bounds = [(smallest_positive_float, np.inf),
#               (smallest_positive_float, np.inf),
#               (-np.inf, np.inf)]
# exp_bounds = [(0, np.inf),
#               (0, np.inf),
#               (-np.inf, np.inf)]
exp_bounds = [(0, None), (0, None), (None, None)]

linear = DependenceFunction(_linear)
# exp3 = DependenceFunction(_exp3)
exp3 = DependenceFunction(_exp3, bounds=exp_bounds)

rng = np.random.RandomState(42)

x = np.linspace(0.1, 10, num=50)
linear_param = (3.6, 6)
y_linear = linear(x, *linear_param) + 5 * rng.normal(scale=1, size=x.shape)
exp_param = (3, 1, 0.5)
y_exp = exp3(x, *exp_param) + 2 * rng.normal(scale=3, size=x.shape)

my_linear_param = fit_function(linear, x, y_linear, (1, 1), "lsq", None, None)
ref_linear_param = curve_fit(linear, x, y_linear, (1, 1))[0]

exp_p0 = tuple(exp3.parameters.values())
Exemplo n.º 15
0
def test_DNVGL_Hs_Tz_model(dataset_dnvgl_hstz, refdata_dnvgl_hstz):
    # A 3-parameter power function (a dependence function).
    def _power3(x, a, b, c):
        return a + b * x**c

    # A 3-parameter exponential function (a dependence function).
    def _exp3(x, a, b, c):
        return a + b * np.exp(c * x)

    bounds = [(0, None), (0, None), (None, None)]
    power3 = DependenceFunction(_power3, bounds)
    exp3 = DependenceFunction(_exp3, bounds)

    x, dx = np.linspace([0.1, 0.1], [6, 22], num=100, retstep=True)

    dist_description_0 = {
        "distribution": WeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=0.5),
    }
    dist_description_1 = {
        "distribution": LogNormalDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu": power3,
            "sigma": exp3
        },
    }
    ghm = GlobalHierarchicalModel([dist_description_0, dist_description_1])
    ghm.fit(dataset_dnvgl_hstz)
    f_weibull = ghm.distributions[0].pdf(x[:, 0])
    weibull_params = (
        ghm.distributions[0].beta,
        ghm.distributions[0].gamma,
        ghm.distributions[0].alpha,
    )

    lognorm = ghm.distributions[1]
    intervals = lognorm.data_intervals
    givens = lognorm.conditioning_values
    f_lognorm = []
    for given in givens:
        f_lognorm.append(lognorm.pdf(x[:, 1], given))

    f_lognorm = np.stack(f_lognorm, axis=1)
    mus = np.array([par["mu"] for par in lognorm.parameters_per_interval])
    sigmas = np.array(
        [par["sigma"] for par in lognorm.parameters_per_interval])

    ref_f_weibull = refdata_dnvgl_hstz["ref_f_weibull"]
    ref_weibull_params = refdata_dnvgl_hstz["ref_weibull_params"]
    ref_intervals = 11
    ref_givens = refdata_dnvgl_hstz["ref_givens"]
    ref_f_lognorm = refdata_dnvgl_hstz["ref_f_lognorm"]
    ref_mus = refdata_dnvgl_hstz["ref_mus"]
    ref_sigmas = refdata_dnvgl_hstz["ref_sigmas"]

    assert len(intervals) == len(ref_intervals)
    for i in range(len(ref_intervals)):
        assert sorted(intervals[i]) == sorted(ref_intervals[i])

    np.testing.assert_allclose(f_weibull, ref_f_weibull)
    np.testing.assert_allclose(weibull_params, ref_weibull_params)
    np.testing.assert_allclose(givens, ref_givens)
    np.testing.assert_allclose(f_lognorm, ref_f_lognorm, rtol=1e-5)
    np.testing.assert_allclose(mus, ref_mus)
    np.testing.assert_allclose(sigmas, ref_sigmas)
Exemplo n.º 16
0
def test_WES4(dataset_wes_sigmau, refdata_wes_sigmau):
    # https://doi.org/10.5194/wes-4-325-2019

    class MyIntervalSlicer(WidthOfIntervalSlicer):
        def _slice(self, data):

            interval_slices, interval_references, interval_boundaries = super(
            )._slice(data)

            # discard slices below 4 m/s
            ok_slices = []
            ok_references = []
            ok_boundaries = []
            for slice_, reference, boundaries in zip(interval_slices,
                                                     interval_references,
                                                     interval_boundaries):
                if reference >= 4:
                    ok_slices.append(slice_)
                    ok_references.append(reference)
                    ok_boundaries.append(boundaries)

            return ok_slices, ok_references, ok_boundaries

    def _poly3(x, a, b, c, d):
        return a * x**3 + b * x**2 + c * x + d

    def _poly2(x, a, b, c):
        return a * x**2 + b * x + c

    poly3 = DependenceFunction(_poly3)
    poly2 = DependenceFunction(_poly2)

    dim0_description = {
        "distribution": WeibullDistribution(),
        "intervals": MyIntervalSlicer(width=1,
                                      reference="left",
                                      min_n_points=5),
    }

    dim1_description = {
        "distribution": LogNormalNormFitDistribution(),
        "conditional_on": 0,
        "parameters": {
            "mu_norm": poly3,
            "sigma_norm": poly2
        },
    }

    ghm = GlobalHierarchicalModel([dim0_description, dim1_description])
    ghm.fit(dataset_wes_sigmau)

    alpha = 1 / (5 * len(dataset_wes_sigmau))
    iform = IFORMContour(ghm, alpha)
    my_coordinates = iform.coordinates

    x_U = np.linspace(2, 40, num=100)
    x_sigma = np.linspace(0.02, 3.6, num=100)

    U_dist = ghm.distributions[0]
    my_weib_param = list(U_dist.parameters.values())
    my_f_weib = U_dist.pdf(x_U)

    my_ln = ghm.distributions[1]
    my_intervals = my_ln.data_intervals
    my_givens = my_ln.conditioning_values
    my_f_ln = []
    for given in my_givens:
        my_f_ln.append(my_ln.pdf(x_sigma, given))

    my_f_ln = np.stack(my_f_ln, axis=1)

    my_mu_norms = np.array(
        [par["mu_norm"] for par in my_ln.parameters_per_interval])
    my_sigma_norms = np.array(
        [par["sigma_norm"] for par in my_ln.parameters_per_interval])
    my_intervals = my_ln.data_intervals
    my_sigmas = [dist.sigma for dist in my_ln.distributions_per_interval]
    my_mus = [dist.mu for dist in my_ln.distributions_per_interval]

    ref_weib_param = refdata_wes_sigmau["ref_weib_param"]
    ref_f_weib = refdata_wes_sigmau["ref_f_weib"]
    ref_intervals = refdata_wes_sigmau["ref_intervals"]
    ref_givens = refdata_wes_sigmau["ref_givens"]
    ref_mu_norms = refdata_wes_sigmau["ref_mu_norms"]
    ref_sigma_norms = refdata_wes_sigmau["ref_sigma_norms"]
    ref_mus = refdata_wes_sigmau["ref_mus"]
    ref_sigmas = refdata_wes_sigmau["ref_sigmas"]
    ref_f_ln = refdata_wes_sigmau["ref_f_ln"]
    ref_coordinates = refdata_wes_sigmau["ref_coordinates"]

    np.testing.assert_allclose(my_weib_param, ref_weib_param)
    np.testing.assert_allclose(my_f_weib, ref_f_weib)

    assert len(my_intervals) == len(ref_intervals)
    for i in range(len(ref_intervals)):
        assert sorted(my_intervals[i]) == sorted(ref_intervals[i])

    np.testing.assert_allclose(my_givens, ref_givens)
    np.testing.assert_allclose(my_mu_norms, ref_mu_norms)
    np.testing.assert_allclose(my_sigma_norms, ref_sigma_norms)
    np.testing.assert_allclose(my_mus, ref_mus)
    np.testing.assert_allclose(my_sigmas, ref_sigmas)
    np.testing.assert_allclose(my_f_ln, ref_f_ln)
    np.testing.assert_allclose(my_coordinates, ref_coordinates)
Exemplo n.º 17
0
def test_OMAE2020(dataset_omae2020_vhs, refdata_omae2020_vhs):
    def _logistics4(x, a=1, b=1, c=-1, d=1):
        return a + b / (1 + np.exp(c * (x - d)))

    def _alpha3(x, a, b, c, d_of_x):
        return (a + b * x**c) / 2.0445**(1 / d_of_x(x))

    logistics_bounds = [(0, None), (0, None), (None, 0), (0, None)]

    alpha_bounds = [(0, None), (0, None), (None, None)]

    beta_dep = DependenceFunction(_logistics4,
                                  logistics_bounds,
                                  weights=lambda x, y: y)
    alpha_dep = DependenceFunction(_alpha3,
                                   alpha_bounds,
                                   d_of_x=beta_dep,
                                   weights=lambda x, y: y)

    dist_description_vs = {
        "distribution": ExponentiatedWeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(width=2),
    }

    dist_description_hs = {
        "distribution": ExponentiatedWeibullDistribution(f_delta=5),
        "conditional_on": 0,
        "parameters": {
            "alpha": alpha_dep,
            "beta": beta_dep,
        },
    }

    ghm = GlobalHierarchicalModel([dist_description_vs, dist_description_hs])

    fit_description_vs = {"method": "wlsq", "weights": "quadratic"}
    fit_description_hs = {"method": "wlsq", "weights": "quadratic"}

    ghm.fit(dataset_omae2020_vhs, [fit_description_vs, fit_description_hs])

    x = np.linspace([0.1, 0.1], [30, 12], num=100)

    my_f_expweib0 = ghm.distributions[0].pdf(x[:, 0])
    my_expweib0_params = (
        ghm.distributions[0].alpha,
        ghm.distributions[0].beta,
        ghm.distributions[0].delta,
    )

    my_expweib1 = ghm.distributions[1]
    my_givens = my_expweib1.conditioning_values
    my_f_expweib1 = []
    for given in my_givens:
        my_f_expweib1.append(my_expweib1.pdf(x[:, 1], given))

    my_f_expweib1 = np.stack(my_f_expweib1, axis=1)

    my_alphas = np.array(
        [par["alpha"] for par in my_expweib1.parameters_per_interval])
    my_betas = np.array(
        [par["beta"] for par in my_expweib1.parameters_per_interval])
    my_intervals = my_expweib1.data_intervals

    ref_expweib0_params = refdata_omae2020_vhs["ref_expweib0_params"]
    ref_f_expweib0 = refdata_omae2020_vhs["ref_f_expweib0"]
    ref_intervals = refdata_omae2020_vhs["ref_intervals"]
    ref_givens = refdata_omae2020_vhs["ref_givens"]
    ref_alphas = refdata_omae2020_vhs["ref_alphas"]
    ref_betas = refdata_omae2020_vhs["ref_betas"]
    ref_f_expweib1 = refdata_omae2020_vhs["ref_f_expweib1"]

    np.testing.assert_almost_equal(my_expweib0_params, ref_expweib0_params)
    np.testing.assert_almost_equal(my_f_expweib0, ref_f_expweib0)
    for my_interval, ref_interval in zip(my_intervals, ref_intervals):
        np.testing.assert_almost_equal(np.sort(my_interval),
                                       np.sort(ref_interval))
    np.testing.assert_almost_equal(my_givens, ref_givens)
    np.testing.assert_almost_equal(my_alphas, ref_alphas)
    np.testing.assert_almost_equal(my_betas, ref_betas)
    np.testing.assert_almost_equal(my_f_expweib1, ref_f_expweib1)
Exemplo n.º 18
0
def get_OMAE2020_V_Hs():
    """
    Get OMAE2020 wind speed and significant wave height model.
    
    Get the descriptions necessary to create the wind speed and 
    significant wave height model as described by Haselsteiner et al. [1]_. 
    
    Returns
    -------
    dist_descriptions : list of dict
        List of dictionaries containing the dist descriptions for each dimension.
        Can be used to create a GlobalHierarchicalModel.
    fit_descriptions : list of dict
        List of dictionaries containing the fit description for each dimension.
        Can be passed to fit function of GlobalHierarchicalModel.
    semantics : dict
        Dictionary with a semantic description of the model.
        Can be passed to plot functions.
        
    References
    ----------
    .. [1] Haselsteiner, A.F.; Sander, A.; Ohlendorf, J.H.; Thoben, K.D. (2020)
        Global hierarchical models for wind and wave contours: Physical
        interpretations of the dependence functions. OMAE 2020, Fort Lauderdale,
        USA. Proceedings of the 39th International Conference on Ocean, 
        Offshore and Arctic Engineering.
    """

    def _logistics4(x, a=1, b=1, c=-1, d=1):
        return a + b / (1 + np.exp(c * (x - d)))

    def _alpha3(x, a, b, c, d_of_x):
        return (a + b * x ** c) / 2.0445 ** (1 / d_of_x(x))

    logistics_bounds = [(0, None), (0, None), (None, 0), (0, None)]

    alpha_bounds = [(0, None), (0, None), (None, None)]

    beta_dep = DependenceFunction(_logistics4, logistics_bounds, weights=lambda x, y: y)
    alpha_dep = DependenceFunction(
        _alpha3, alpha_bounds, d_of_x=beta_dep, weights=lambda x, y: y
    )

    dist_description_v = {
        "distribution": ExponentiatedWeibullDistribution(),
        "intervals": WidthOfIntervalSlicer(2, min_n_points=50),
    }

    dist_description_hs = {
        "distribution": ExponentiatedWeibullDistribution(f_delta=5),
        "conditional_on": 0,
        "parameters": {"alpha": alpha_dep, "beta": beta_dep,},
    }

    dist_descriptions = [dist_description_v, dist_description_hs]

    fit_description_v = {"method": "wlsq", "weights": "quadratic"}
    fit_description_hs = {"method": "wlsq", "weights": "quadratic"}
    fit_descriptions = [fit_description_v, fit_description_hs]

    semantics = {
        "names": ["Mean wind speed", "Significant wave height"],
        "symbols": ["V", "H_s"],
        "units": ["m s$^{-1}$", "m",],
    }

    return dist_descriptions, fit_descriptions, semantics
Exemplo n.º 19
0
                ok_references.append(reference)
                ok_boundaries.append(boundaries)

        return ok_slices, ok_references, ok_boundaries


# %%
def _poly3(x, a, b, c, d):
    return a * x**3 + b * x**2 + c * x + d


def _poly2(x, a, b, c):
    return a * x**2 + b * x + c


poly3 = DependenceFunction(_poly3)
poly2 = DependenceFunction(_poly2)

dim0_description = {
    "distribution": WeibullDistribution(),
    "intervals": MyIntervalSlicer(width=1, reference="left", min_n_points=5),
    # "parameters" : {"alpha" : 9.74,
    #                 "beta" : 2.02,
    #                 "gamma" : 2.2},
}

dim1_description = {
    "distribution": LogNormalNormFitDistribution(),
    "conditional_on": 0,
    "parameters": {
        "mu_norm": poly3,