HN derivative Module

HN_derivative class

class HavNegpy.HN_derivative[source]

A class to analyze the derivaite of real part of complex permittivity with derivative HN function

Fit functions include single, double, and derivative HN with electrode polarization

HavNegpy.HN_derivative fit functions

HN_derivative.deri_hn(x, b, g, fm, deps)[source]

derivaitive HN fit function to fit single peak

Parameters
  • x (float) – frequency.

  • b (float) – symmetric fractional parameter.

  • g (float) – asymmetric fractional parameter.

  • fm (float) – maximum frequency of the peak.

  • deps (float) – dielectric strength.

Returns

y – estimated log derivative of epsilon’ based on the supplied parameters.

Return type

array

HN_derivative.deri_hn_ep(x, b, g, fm, deps, A, l)[source]

derivaitive HN fit function to fit single peak along with electrode polarization(ep)

Parameters
  • x (float) – frequency.

  • b (float) – symmetric fractional parameter.

  • g (float) – asymmetric fractional parameter.

  • fm (float) – maximum frequency of the loss peak.

  • deps (float) – dielectric strength.

  • A (float) – electrode polarization value.

  • l (float) – power law exponent.

Returns

y – estimated log derivative of epsilon’ based on the supplied parameters.

Return type

array

HN_derivative.deri_double_hn(x, b1, g1, fm1, deps1, b2, g2, fm2, deps2)[source]

derivaitive HN fit function to fit two peaks

Parameters
  • x (float) – frequency.

  • b1 (float) – symmetric fractional parameter of the 1st peak.

  • g1 (float) – asymmetric fractional parameter of the 1st peak.

  • fm1 (float) – maximum frequency of the 1st peak.

  • deps1 (float) – dielectric strength of the 1st peak.

  • b2 (float) – symmetric fractional parameter of the 2nd peak.

  • g2 (float) – asymmetric fractional parameter of the 2nd peak.

  • fm2 (float) – maximum frequency of the 2nd peak.

  • deps2 (float) – dielectric strength of the 2nd peak.

Returns

y – estimated log derivative of epsilon’ based on the supplied parameters.

Return type

array

HN_derivative.ep_s(x, A, l)[source]

Function to estimate the electrode polarization(EP) contribution from the total fit

While fitting, the deconvoluted EP is based on this function.

Parameters
  • x (float) – frequency.

  • A (float) – electrode polarization value.

  • l (float) – power law exponent.

Returns

y – estimated log EP.

Return type

array

HavNegpy.HN_derivative dump methods

HN_derivative.dump_parameters_deri_hn()[source]

dumps the initial fit parameters for derivative hn function as a dictionary in a json file to load it during curve fitting

Return type

None

HN_derivative.dump_parameters_deri_double_hn()[source]

dumps the initial fit parameters for derivative_double hn function as a dictionary in a json file to load it during curve fitting

Return type

None

HavNegpy.HN_derivative initial view methods

HN_derivative.initial_view_deri_hn(x, y)[source]

plots the derivative hn function based on the initial parameters given via the dump_parameters method

Parameters
  • x (array) – log frequency.

  • y (array) – log derivative of epsilon’.

Return type

None.

HN_derivative.initial_view_deri_hn_ep(x, y)[source]

plots the derivative hn function with electrode polarization based on the initial parameters given via the dump_parameters method

Parameters
  • x (array) – log frequency.

  • y (array) – log derivative of epsilon’.

Return type

None.

HN_derivative.initial_view_deri_double_hn(x, y)[source]

plots the derivative double hn function based on the initial parameters given via the dump_parameters method

Parameters
  • x (array) – log frequency.

  • y (array) – log derivative of epsilon’.

Return type

None.

HavNegpy.HN_derivaitve methods for fitting and saving the fit results

HN_derivative.create_analysis_file()[source]

Creates a file to save the fit results based on the choice of fit function

Provides option to use an existing file and creates a new file if not found

Return type

None.

HN_derivative.select_range(x, y)[source]

Selects the region of interest to fit data using mplcursors allows two clicks to select the lower and upper bound of the x-axis and returns the selected x and y vaues for fitting

Returns

  • x1 (array) – log frequency

  • y1 (array) – log dielectric loss

HN_derivative.fit(x, y)[source]

Fits the derivaitve of epsilon’ data with choice of fit function The fit parameters are declared as global variables to be saved via save_fit function

The initial fit parameters are taken from json file and the final fit parameters are dumped in the same json file to be used for next iteration.

Parameters
  • x (array) – log frequency.

  • y (array) – log dielectric loss.

Returns

fit_par – dictionary containing the fit parameters.

Return type

dictionary

HN_derivative.save_fit_deri_hn(T)[source]

saves the fit parameters of derivative hn function in a file the file must be created via create_analysis_file function

Parameters

T (float) – Temperature,or can also be an integer that corresponds to a file number during analysis.

Return type

None.

HN_derivative.save_fit_deri_hn_ep(T)[source]

saves the fit parameters of derivaitve hn function with electrode polarization in a file, the file must be created via create_analysis_file function

Parameters

T (float) – Temperature,or can also be an integer that corresponds to a file number during analysis.

Return type

None.

HN_derivative.save_fit_deri_double_HN(T)[source]

saves the fit parameters of derivaitve double hn function in a file, the file must be created via create_analysis_file function

Parameters

T (float) – Temperature,or can also be an integer that corresponds to a file number during analysis.

Return type

None.