Python lmfit.Model方法代码示例

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def nena(locs, info, callback=None):
    bin_centers, dnfl_ = next_frame_neighbor_distance_histogram(locs, callback)

    def func(d, a, s, ac, dc, sc):
        f = a * (d / s ** 2) * _np.exp(-0.5 * d ** 2 / s ** 2)
        fc = (
            ac
            * (d / sc ** 2)
            * _np.exp(-0.5 * (d ** 2 + dc ** 2) / sc ** 2)
            * _iv(0, d * dc / sc)
        )
        return f + fc

    pdf_model = _lmfit.Model(func)
    params = _lmfit.Parameters()
    area = _np.trapz(dnfl_, bin_centers)
    median_lp = _np.mean([_np.median(locs.lpx), _np.median(locs.lpy)])
    params.add("a", value=area / 2, min=0)
    params.add("s", value=median_lp, min=0)
    params.add("ac", value=area / 2, min=0)
    params.add("dc", value=2 * median_lp, min=0)
    params.add("sc", value=median_lp, min=0)
    result = pdf_model.fit(dnfl_, params, d=bin_centers)
    return result, result.best_values["s"] 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_base_param_decay(x: np.ndarray, y: np.ndarray, weights: np.ndarray = None,
                         param_guesses: tuple = (1., .9, 0.)) -> ModelResult:
    """
    Fit experimental data x, y to an exponential decay parameterized by a base decay parameter.

    :param x: The independent variable, e.g. depth or time
    :param y: The dependent variable, e.g. survival probability
    :param weights: Optional weightings of each point to use when fitting.
    :param param_guesses: initial guesses for the parameters
    :return: a lmfit Model
    """
    _check_data(x, y, weights)
    decay_model = Model(base_param_decay)
    params = decay_model.make_params(amplitude=param_guesses[0], decay=param_guesses[1],
                                     baseline=param_guesses[2])
    return decay_model.fit(y, x=x, params=params, weights=weights) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_decay_time_param_decay(x: np.ndarray, y: np.ndarray, weights: np.ndarray = None,
                               param_guesses: tuple = (1., 10, 0)) -> ModelResult:
    """
    Fit experimental data x, y to an exponential decay parameterized by a decay time, or inverse
    decay rate.

    :param x: The independent variable, e.g. depth or time
    :param y: The dependent variable, e.g. survival probability
    :param weights: Optional weightings of each point to use when fitting.
    :param param_guesses: initial guesses for the parameters
    :return: a lmfit Model
    """
    _check_data(x, y, weights)
    decay_model = Model(decay_time_param_decay)
    params = decay_model.make_params(amplitude=param_guesses[0], decay_time=param_guesses[1],
                                     offset=param_guesses[2])
    return decay_model.fit(y, x=x, params=params, weights=weights) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_decaying_cosine(x: np.ndarray, y: np.ndarray, weights: np.ndarray = None,
                        param_guesses: tuple = (.5, 10, 0.0, 0.5, 5)) -> ModelResult:
    """
    Fit experimental data x, y to an exponentially decaying cosine.

    :param x: The independent variable, e.g. depth or time
    :param y: The dependent variable, e.g. probability of measuring 1
    :param weights: Optional weightings of each point to use when fitting.
    :param param_guesses: initial guesses for the parameters
    :return: a lmfit Model
    """
    _check_data(x, y, weights)
    decay_model = Model(decaying_cosine)
    params = decay_model.make_params(amplitude=param_guesses[0], decay_time=param_guesses[1],
                                     offset=param_guesses[2], baseline=param_guesses[3],
                                     frequency=param_guesses[4])
    return decay_model.fit(y, x=x, params=params, weights=weights) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_shifted_cosine(x: np.ndarray, y: np.ndarray, weights: np.ndarray = None,
                       param_guesses: tuple = (.5, 0, .5, 1.)) -> ModelResult:
    """
    Fit experimental data x, y to a cosine shifted vertically by amount baseline.

    :param x: The independent variable, e.g. depth or time
    :param y: The dependent variable, e.g. probability of measuring 1
    :param weights: Optional weightings of each point to use when fitting.
    :param param_guesses: initial guesses for the parameters
    :return: a lmfit Model
    """
    _check_data(x, y, weights)
    decay_model = Model(shifted_cosine)
    params = decay_model.make_params(amplitude=param_guesses[0], offset=param_guesses[1],
                                     baseline=param_guesses[2],
                                     frequency=param_guesses[3])
    return decay_model.fit(y, x=x, params=params, weights=weights) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def bridge_function2(x, center1, center2, sigma1, sigma2, amplitude):
    """A "bridge" function, geometric complementary of two gaussian peaks.

    Let `g` be a Gaussian function (with amplitude = 1), the bridge function
    is defined as:

        amplitude * (1 - g(x, center1, sigma1)) * (1 - g(x, center2, sigma2))

    for center1 < x < center2. The function is 0 otherwise.

    Arguments:
        x (array): 1-D array for the independent variable
        center1 (float): center of the first gaussian (left side)
        center2 (float): center of the second gaussian (right side)
        sigma1 (float): sigma of the left-side gaussian
        sigma2 (float): sigma of the right-side gaussian
        amplitude (float): maximum (asymptotic) value of the bridge (plateau)

    Return:
        An array (same shape as `x`) with the function values.
    """
    assert center1 <= center2
    assert amplitude >= 0
    mask = (x > center1)*(x < center2)
    y = np.zeros_like(x)
    y[mask] = amplitude
    y[mask] *= 1 - gaussian(x[mask], center1, sigma1)
    y[mask] *= 1 - gaussian(x[mask], center2, sigma2)
    y *= amplitude
    return y


##
# Factory functions that return initialized `lmfit.Model` objects
# 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def factory_gaussian(center=0.1, sigma=0.1, amplitude=1):
    """Return an lmfit Gaussian model that can be used to fit data.

    Arguments are initial values for the model parameters.

    Returns
        An `lmfit.Model` object with all the parameters already initialized.
    """
    model = lmfit.models.GaussianModel()
    model.set_param_hint('center', value=center, min=-1, max=2)
    model.set_param_hint('sigma', value=sigma)
    model.set_param_hint('amplitude', value=amplitude)
    return model 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def factory_asym_gaussian(center=0.1, sigma1=0.1, sigma2=0.1, amplitude=1):
    """Return a lmfit Asymmetric Gaussian model that can be used to fit data.

    For the definition of asymmetric Gaussian see :func:`asym_gaussian`.
    Arguments are initial values for the model parameters.

    Returns
        An `lmfit.Model` object with all the parameters already initialized.
    """
    model = lmfit.model.Model(asym_gaussian)
    model.set_param_hint('center', value=center, min=-1, max=2)
    model.set_param_hint('sigma1', value=sigma1)
    model.set_param_hint('sigma2', value=sigma2)
    model.set_param_hint('amplitude', value=amplitude)
    return model 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def factory_three_gaussians(p1_center=0., p2_center=0.5, p3_center=1,
                            sigma=0.05):
    """Return a 3-Gaussian model that can fit data.

    The other arguments are initial values for the `center` for each
    Gaussian component plus an single `sigma` argument that is used
    as initial sigma for all the Gaussians. Note that during the fitting
    the sigma of each Gaussian is varied independently.

    Returns
        An `lmfit.Model` object with all the parameters already initialized.
    """
    peak1 = lmfit.models.GaussianModel(prefix='p1_')
    peak2 = lmfit.models.GaussianModel(prefix='p2_')
    peak3 = lmfit.models.GaussianModel(prefix='p3_')
    model = peak1 + peak2 + peak3

    model.set_param_hint('p1_center', value=p1_center, min=0, max=1)
    model.set_param_hint('p2_center', value=p2_center, min=0, max=1)
    model.set_param_hint('p3_center', value=p3_center, min=0, max=1)
    model.set_param_hint('p1_sigma', value=sigma, min=0.02, max=0.2)
    model.set_param_hint('p2_sigma', value=sigma, min=0.02, max=0.2)
    model.set_param_hint('p3_sigma', value=sigma, min=0.02, max=0.2)
    model.set_param_hint('p1_amplitude', value=1, min=0.01)
    model.set_param_hint('p2_amplitude', value=1, min=0.01)
    model.set_param_hint('p3_amplitude', value=1, min=0.01)
    model.name = '3-gaussians'
    return model

## lmfit composite model used for fitting 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_histogram(self, model=None, pdf=True, **fit_kwargs):
        """Fit the histogram of each channel using the same lmfit model.

        A list of `lmfit.Minimizer` is stored in `.fit_res`.
        The fitted values for all the parameters and all the channels are
        save in a Pandas DataFrame `.params`.

        Arguments:
            model (lmfit.Model object): lmfit Model with all the parameters
                already initialized used for fitting.
            pdf (bool): if True fit the normalized histogram (.hist_pdf)
                otherwise fit the raw counts (.hist_counts).
            fit_kwargs (dict): keyword arguments passed to `model().fit`.
        """
        if model is not None:
            self.model = model
        if not self._hist_computed:
            self.histogram()

        data_list = self.hist_pdf if pdf else self.hist_counts
        self.params = pd.DataFrame(index=range(self.ndata),
                                   columns=sorted(self.model.param_names))
        self.fit_res = []
        #init_params = copy.deepcopy(self.model.params)
        for i, data in enumerate(data_list):
            self.fit_res.append(
                self.model.fit(data, x=self.hist_axis, **fit_kwargs))
            self.params.iloc[i] = pd.Series(self.fit_res[-1].values) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def emp_jacobian(pars, x, y):
    """
    An empirical calculation of the Jacobian
    Will work for a model that contains multiple Gaussians, and for which
    some components are not being fit (don't vary).

    Parameters
    ----------
    pars : lmfit.Model
        The model parameters
    x, y : list
        Locations at which the jacobian is being evaluated

    Returns
    -------
    j : 2d array
        The Jacobian.

    See Also
    --------
    :func:`AegeanTools.fitting.jacobian`
    """
    eps = 1e-5
    matrix = []
    model = ntwodgaussian_lmfit(pars)(x, y)
    for i in range(pars['components'].value):
        prefix = "c{0}_".format(i)
        for p in ['amp', 'xo', 'yo', 'sx', 'sy', 'theta']:
            if pars[prefix + p].vary:
                pars[prefix + p].value += eps
                dmdp = ntwodgaussian_lmfit(pars)(x, y) - model
                matrix.append(dmdp / eps)
                pars[prefix + p].value -= eps
    matrix = np.array(matrix)
    return matrix 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def base_param_decay(x: np.ndarray, amplitude: float, decay: float, baseline: float):
    """
    Model an exponential decay parameterized by a base parameter raised to the power of the
    independent variable x.

    :param numpy.ndarray x: Independent variable
    :param float baseline: Offset value
    :param float amplitude: Amplitude of exponential decay
    :param float decay: Decay parameter
    :return: Exponential decay fit function
    """
    return np.asarray(baseline + amplitude * decay ** x) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def decay_time_param_decay(x: np.ndarray, amplitude: float, decay_time: float,
                           offset: float = 0.0) -> np.ndarray:
    """
    Model an exponential decay parameterized by a decay constant with constant e as the base.

    :param x: The independent variable with respect to which decay is calculated.
    :param amplitude: The amplitude of the decay curve.
    :param decay_time: The inverse decay rate - e.g. T1 - of the decay curve.
    :param offset: The offset of the curve, (typically take to be 0.0).
    :return: Exponential decay fit function, parameterized with a decay constant
    """
    return np.asarray(amplitude * np.exp(-1 * (x - offset) / decay_time)) 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def fit_pixel_nonlinear_per_line(row_num, data, x0,
                                 param, reg_mat,
                                 use_snip):  # c_weight, fit_num, ftol):

    # c_weight = 1
    # fit_num = 100
    # ftol = 1e-3

    elist = param['non_fitting_values']['element_list'].split(', ')
    elist = [e.strip(' ') for e in elist]

    # LinearModel = lmfit.Model(simple_spectrum_fun_for_nonlinear)
    # for i in np.arange(reg_mat.shape[0]):
    #     LinearModel.set_param_hint('a'+str(i), value=0.1, min=0, vary=True)

    logger.info('Row number at {}'.format(row_num))
    out = []
    snip_bg = 0
    for i in range(data.shape[0]):
        if use_snip is True:
            bg = snip_method_numba(data[i, :],
                                   param['e_offset']['value'],
                                   param['e_linear']['value'],
                                   param['e_quadratic']['value'],
                                   width=param['non_fitting_values']['background_width'])
            y0 = data[i, :] - bg
            snip_bg = np.sum(bg)
        else:
            y0 = data[i, :]

        fit_params = lmfit.Parameters()
        for i in range(reg_mat.shape[1]):
            fit_params.add('a'+str(i), value=1.0, min=0, vary=True)

        result = lmfit.minimize(residual_nonlinear_fit,
                                fit_params, args=(x0,),
                                kws={'data': y0, 'reg_mat': reg_mat})

        # result = MS.model_fit(x0, y0,
        #                       weights=1/np.sqrt(c_weight+y0),
        #                       maxfev=fit_num,
        #                       xtol=ftol, ftol=ftol, gtol=ftol)
        # namelist = list(result.keys())
        temp = {}
        temp['value'] = [result.params[v].value for v in list(result.params.keys())]
        temp['err'] = [result.params[v].stderr for v in list(result.params.keys())]
        temp['snip_bg'] = snip_bg
        out.append(temp)
    return out 

# 需要导入模块: import lmfit [as 别名]
# 或者: from lmfit import Model [as 别名]
def factory_two_gaussians(add_bridge=False, p1_center=0.1, p2_center=0.9,
                          p1_sigma=0.03, p2_sigma=0.03):
    """Return a 2-Gaussian + (optional) bridge model that can fit data.

    The optional "bridge" component (i.e. a plateau between the two peaks)
    is a function that is non-zero only between `p1_center` and `p2_center`
    and is defined as::

        br_amplitude * (1 - g(x, p1_center, p1_sigma) - g(x, p1_center, p2_sigma))

    where `g` is a gaussian function with amplitude = 1 and `br_amplitude`
    is the height of the plateau and the only additional parameter introduced
    by the bridge. Note that both centers and sigmas parameters in the bridge
    are the same ones of the adjacent Gaussian peaks. Therefore a
    2-Gaussian + bridge model has 7 free parameters: 3 for each Gaussian and
    an additional one for the bridge.
    The bridge function is implemented in :func:`bridge_function`.

    Arguments:
        p1_center, p2_center (float): initial values for the centers of the
            two Gaussian components.
        p1_sigma, p2_sigma (float): initial values for the sigmas of the
            two Gaussian components.
        add_bridge (bool): if True adds a bridge function between the two
            gaussian peaks. If False the model has only two Gaussians.

    Returns
        An `lmfit.Model` object with all the parameters already initialized.
    """
    peak1 = lmfit.models.GaussianModel(prefix='p1_')
    peak2 = lmfit.models.GaussianModel(prefix='p2_')
    model = peak1 + peak2

    model.set_param_hint('p1_center', value=p1_center, min=-1, max=2)
    model.set_param_hint('p2_center', value=p2_center, min=-1, max=2)
    model.set_param_hint('p1_sigma', value=p1_sigma, min=0.01, max=0.2)
    model.set_param_hint('p2_sigma', value=p2_sigma, min=0.01, max=0.2)
    model.set_param_hint('p1_amplitude', value=1, min=0.01)
    model.set_param_hint('p2_amplitude', value=1, min=0.01)
    name = '2-gaussians'

    if add_bridge:
        bridge = lmfit.model.Model(bridge_function, prefix='br_')
        model += bridge
        model.set_param_hint('br_amplitude', value=0.0001, min=0)
        model.set_param_hint('br_center1', min=0, expr='p1_center')
        model.set_param_hint('br_center2', min=0, expr='p2_center')
        model.set_param_hint('br_sigma1', min=0, expr='p1_sigma')
        model.set_param_hint('br_sigma2', min=0, expr='p2_sigma')
        name += '-bridge'
    model.name = name
    return model