5.1.4.0 sd.fitter.set_lorentz_parameters

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sd.fitter.set_lorentz_parameters - Function

5.1.4 Set the parameters of Lorentzian component
Description

Set the Parameters of a ’Lorentzian’ component, set with set_function.

Three arguments, peak, centre, and fwhm, are mandatory to be set. They specifies an initial model of Lorentzian component.

The peakfixed, centrefixed, and fwhmfixed are optional parameters to indicate if the paramters should be held fixed during the fitting process. The default is to keep all parameters flexible. If you want to fix one of those parameters, you can do it by setting corresponding arguments (peakfixed, centrefixed, and fwhmfixed) to 1.

The component argument is only effective for multi-component Lorentzian fitting. It specifies the number of the component to set the specified parameters.

Arguments


Inputs
peak	The lorentzian parameters (peak intensity)
	allowed:	float
	Default:
centre	The lorentzian parameters (line center)
	allowed:	float
	Default:
fwhm	The lorentzian parameters (FWHM)
	allowed:	float
	Default:
peakfixed	Optional parameters to indicate if peak should be held fixed during the fitting process
	allowed:	integer
	Default:	0 (flexible)
centrefixed	Optional parameters to indicate if centre should be held fixed during the fitting process
	allowed:	integer
	Default:	0 (flexible)
fwhmfixed	Optional parameters to indicate if fwhm should be held fixed during the fitting process
	allowed:	integer
	Default:	0 (flexible)
component	The number of the component
	allowed:	integer
	Default:	0

Returns

Example

   f=sd.fitter()
   s=sd.scantable(’OrionS_rawACSmod_cal’,average=False)
   f.set_scan(s)
   # set fit function as lorentzian
   f.set_function(lorentz=1)
   # set lorentzian parameter with centre fixed
   f.set_lorentz_parameters(peak=0.5,centre=4100,fwhm=200,centrefixed=1)
   f.fit()

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