HDF5_BLS_analyse.Analyse_VIPA

class HDF5_BLS_analyse.Analyse_VIPA(x, y)

Bases: Analyse_general

This class is a child class of Analyse_general. It inherits all the methods of the parent class and adds the functions specific to VIPA spectrometers.

__init__(x, y)

Initializes the class with the most basic attributes: the ordinates and abscissa of the data.

Parameters:

• y (array) – The array of ordinates of the data

• x (array, optional) – The array of abscissa of the data. If None, the abscissa is just the index of the points in ordinates.

Methods

__init__(x, y)	Initializes the class with the most basic attributes: the ordinates and abscissa of the data.
add_point([position_center_window, ...])	Adds a single point to the list of points together with a window to the list of windows with its type.
center_x_axis([center_type])	Centers the x axis using the first points stored in the class.
interpolate_between_one_order([FSR])	Creates a frequency axis by using the signal between two elastic peaks included.
interpolate_elastic([FSR])	Uses positions of the elastic peaks on the different orders, to obtain a frequency axis by interpolating the position of the peaks with a quadratic polynomial.
interpolate_elastic_inelastic([shift, FSR])	Uses the elastic peaks, and the positions of the Brillouin peaks on the different orders to obtain a frequency axis by interpolating the position of the peaks with a quadratic polynomial.
interpolate_on_one_order([shift])	Uses positions of one elastic peak and associated Brillouin doublet to obtain a frequency axis by interpolating the position of the peak with a quadratic polynomial.
set_x_y(x, y)	Sets the x and y values of the data
silent_clear_points()	Clears the list of points and the list of windows.
silent_create_algorithm([algorithm_name, ...])	Creates a new JSON algorithm with the given name, version, author and description.
silent_move_step(step, new_step)	Moves a step from one position to another in the _algorithm attribute.
silent_open_algorithm([filepath, algorithm_str])	Opens an existing JSON algorithm and stores it in the _algorithm attribute.
silent_remove_step([step])	Removes the step from the _history attribute of the class.
silent_return_string_algorithm()	Returns a string representation of the algorithm stored in the _algorithm attribute of the class.
silent_run_algorithm([step])	Runs the algorithm stored in the _algorithm attribute of the class up to the given step (included).
silent_save_algorithm([filepath, ...])	Saves the algorithm to a JSON file with or without the parameters used.

add_point(position_center_window: float = 0, window_width: float = 0, type_pnt: str = 'Elastic')

Adds a single point to the list of points together with a window to the list of windows with its type. Each point is an intensity extremum obtained by fitting a quadratic polynomial to the windowed data. The point is given as a value on the x axis (not a position). The “position_center_window” parameter is the center of the window surrounding the peak. The “window_width” parameter is the width of the window surrounding the peak (full width). The “type_pnt” parameter is the type of the peak. It can be either “Stokes”, “Anti-Stokes” or “Elastic”.

Parameters:

• position_center_window (float) – A value on the self.x axis corresponding to the center of a window surrounding a peak

• window (float) – A value on the self.x axis corresponding to the width of a window surrounding a peak

• type_pnt (str) – The nature of the peak. Must be one of the following: “Stokes”, “Anti-Stokes” or “Elastic”

center_x_axis(center_type: str = None)

Centers the x axis using the first points stored in the class. The parameter “center_type” is used to determine wether to center the axis using the first elastic peak (center_type = “Elastic”) or the average of two Stokes and Anti-Stokes peaks (center_type = “Inelastic”).

Parameters:

center_type (str) – The type of the peak to center the x axis around. Must be either “Elastic” or “Inelastic”.

interpolate_between_one_order(FSR: float = None)

Creates a frequency axis by using the signal between two elastic peaks included. By imposing that the distance in frequency between two neighboring elastic peaks is one FSR, and that the shift of both stokes and anti-stokes peaks to their respective elastic peak is the same, we can obtain a frequency axis. The user has to enter a value for the FSR to calibrate the frequency axis.

Parameters:

FSR (float) – The free spectral range of the VIPA spectrometer (in GHz).

interpolate_elastic(FSR: float = None)

Uses positions of the elastic peaks on the different orders, to obtain a frequency axis by interpolating the position of the peaks with a quadratic polynomial. The user has to enter a value for the FSR to calibrate the frequency axis.

Parameters:

FSR (float) – The free spectral range of the VIPA spectrometer (in GHz).

interpolate_elastic_inelastic(shift: float = None, FSR: float = None)

Uses the elastic peaks, and the positions of the Brillouin peaks on the different orders to obtain a frequency axis by interpolating the position of the peaks with a quadratic polynomial. The user can either enter a value for the shift or the FSR, or both. The shift value is used to calibrate the frequency axis using known values of shifts when using a calibration sample to obtain the frequency axis. The FSR value is used to calibrate the frequency axis using a known values of FSR for the VIPA.

Parameters:

• shift (float) – The shift between the elastic and inelastic peaks (in GHz).

• FSR (float) – The free spectral range of the VIPA spectrometer (in GHz).

interpolate_on_one_order(shift: float = 1)

Uses positions of one elastic peak and associated Brillouin doublet to obtain a frequency axis by interpolating the position of the peak with a quadratic polynomial. The user has to enter a value for the Brillouin shift to calibrate the frequency axis. By default, this value is set to 1 so that the measured frequencies are normalized to the calibration sample.

Parameters:

shift (float) – The frequency shift between the elastic and inelastic peaks (in GHz). By default 1.