resins.models.panther_abins

The AbINS model of the PANTHER instrument.

All classes within are exposed for reference only and should not be instantiated directly. For obtaining the resolution function of an instrument, please use the resins.instrument.Instrument.get_resolution_function method.

class resins.models.panther_abins.PantherAbINSModel(model_data: PantherAbINSModelData, e_init: float | None = None, **_)

Bases: GaussianKernel1DMixin, SimpleBroaden1DMixin, InstrumentModel

Model for the PANTHER instrument originating from the AbINS software.

Models the resolution as a function of energy transfer (frequencies) only, with the output model being a Gaussian. This is done by fitting three power-series polynomials (see numpy.polynomial.polynomial.Polynomial) to the resolution curve, where the result of the sum of the polynomials is the width (sigma) of the Gaussian. Each polynomial can be of any degree and is given via the resins.models.polynomial.PolynomialModelData.

The resolution is modelled as:

resolution = Polynomial(model_data.abs)(frequencies) +
             Polynomial(model_data.ei_dependence)(e_init) +
             Polynomial(model_data.ei_energy_product)(e_init * frequencies)

where e_init is the initial energy, frequencies is the energy transfer, and model_data is an instance of PantherAbINSModelData.

Parameters:

model_data: The data associated with the model for a given version of a given instrument.
e_init: The incident energy in meV.

Attributes:

input: The names of the columns in the omega_q array expected by all computation methods, i.e. the names of the independent variables ([Q, w]) that the model models.
data_class: Data for the PantherAbINSModel model.
absnumpy.polynomial.polynomial.Polynomial: The energy transfer polynomial.
ei_dependencefloat: The e_init contribution to the resolution.
ei_energy_productnumpy.polynomial.polynomial.Polynomial: The energy transfer and e_init product polynomial.
citation: The citation for this model.

Methods

`__call__`(points, data, *meshes)	Broadens the `data` on the `meshes`.
`broaden`(points, data, mesh)	Broadens the `data` on the full `mesh` using the straightforward scheme.
`data_class`
`get_characteristics`(points)	Computes the broadening width at each value of energy transfer given by `points`.
`get_kernel`(points, mesh)	Computes the Gaussian kernel centered on zero on the provided `mesh` at each (energy transfer or momentum scalar) point in `points`.
`get_peak`(points, mesh)	Computes the Gaussian broadening peak on the provided `mesh` at each (energy transfer or momentum scalar) point in `points`.

data_class: alias of PantherAbINSModelData

get_characteristics(points: Float[np.ndarray, 'energy_transfer dimension=1']) → dict[str, Float[np.ndarray, 'sigma']]

Computes the broadening width at each value of energy transfer given by points.

The model approximates the broadening using the Gaussian distribution, so the returned widths are in the form of the standard deviation (sigma).

Parameters:

points: The energy transfer in meV at which to compute the width in sigma of the kernel. This must be a sample x 1 2D array where sample is the number of energy transfers.

Returns:

characteristics: The characteristics of the broadening function, i.e. the Gaussian width as sigma in meV.

class resins.models.panther_abins.PantherAbINSModelData(*, function: str, citation: list[str], defaults: dict[str, int | float], restrictions: dict[str, list[int | float], set[int | float]], abs: list[float], ei_dependence: list[float], ei_energy_product: list[float])

Bases: ModelData

Data for the PantherAbINSModel model.

Attributes:

function: The name of the function, i.e. the alias for PantherAbINSModel.
citation: The citation for the model. Please use this to look up more details and cite the model.
restrictions: All constraints that the model places on the settings. If the value is a list, this signifies the range style (start, stop, step) tuple, and if it is a set, it is a set of explicitly allowed values.
defaults: The default values for the settings, used when a value is not provided when creating the model.
abs: Polynomial coefficients for the energy transfer (frequencies) polynomial.
ei_dependence: Polynomial coefficients for the initial energy polynomial.
ei_energy_product: Polynomial coefficients for the product of initial energy and energy transfer (frequencies) polynomial.