hyperspy._signals.dielectric_function module

class hyperspy._signals.dielectric_function.DielectricFunction(*args, **kwargs)

Bases: hyperspy._signals.complex_signal1d.ComplexSignal1D

Create a Signal from a numpy array.

Parameters
  • data (numpy.ndarray) – The signal data. It can be an array of any dimensions.

  • axes ([dict/axes], optional) – List of either dictionaries or axes objects to define the axes (see the documentation of the AxesManager class for more details).

  • attributes (dict, optional) – A dictionary whose items are stored as attributes.

  • metadata (dict, optional) – A dictionary containing a set of parameters that will to stores in the metadata attribute. Some parameters might be mandatory in some cases.

  • original_metadata (dict, optional) – A dictionary containing a set of parameters that will to stores in the original_metadata attribute. It typically contains all the parameters that has been imported from the original data file.

  • ragged (bool or None, optional) – Define whether the signal is ragged or not. Overwrite the ragged value in the attributes dictionary. If None, it does nothing. Default is None.

get_number_of_effective_electrons(nat, cumulative=False)

Compute the number of effective electrons using the Bethe f-sum rule.

The Bethe f-sum rule gives rise to two definitions of the effective number (see *), neff1 and neff2:

n_{\mathrm{eff_{1}}} = n_{\mathrm{eff}}\left(-\Im\left(\epsilon^{-1}\right)\right)

and:

n_{\mathrm{eff_{2}}} = n_{\mathrm{eff}}\left(\epsilon_{2}\right)

This method computes and return both.

Parameters

nat (float) – Number of atoms (or molecules) per unit volume of the sample.

Returns

neff1, neff2 – Signal1D instances containing neff1 and neff2. The signal and navigation dimensions are the same as the current signal if cumulative is True, otherwise the signal dimension is 0 and the navigation dimension is the same as the current signal.

Return type

Signal1D

Notes

*

Ray Egerton, “Electron Energy-Loss Spectroscopy in the Electron Microscope”, Springer-Verlag, 2011.

class hyperspy._signals.dielectric_function.LazyDielectricFunction(*args, **kwargs)

Bases: hyperspy._signals.dielectric_function.DielectricFunction, hyperspy._signals.complex_signal1d.LazyComplexSignal1D

Create a Signal from a numpy array.

Parameters
  • data (numpy.ndarray) – The signal data. It can be an array of any dimensions.

  • axes ([dict/axes], optional) – List of either dictionaries or axes objects to define the axes (see the documentation of the AxesManager class for more details).

  • attributes (dict, optional) – A dictionary whose items are stored as attributes.

  • metadata (dict, optional) – A dictionary containing a set of parameters that will to stores in the metadata attribute. Some parameters might be mandatory in some cases.

  • original_metadata (dict, optional) – A dictionary containing a set of parameters that will to stores in the original_metadata attribute. It typically contains all the parameters that has been imported from the original data file.

  • ragged (bool or None, optional) – Define whether the signal is ragged or not. Overwrite the ragged value in the attributes dictionary. If None, it does nothing. Default is None.