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This is an old revision of the document!

Currently defined fit variables
Variable initial lower boundary Initial upper boundary
thickness 0.8*thickness 1.2*thickness
delta -0.1 0.1
beta 0. 0.1
sigma 0. 20
deltam -10*deltam 10*deltam
betam -10*betam 10*betam
angular resolution 0. 0.1
measurement multiplicator 0.1*multiplicator 10*multiplicator
qz translation -1 1
gauss_delta -10*gauss_delta 10*gauss_delta
gauss_beta -10*gauss_beta 10*gauss_beta
gauss_variance 0. 10*gauss_variance
gauss_z -1 1
script variable (par) 0 2

Note: The simplex algorithm will not fit variables with an initial value of 0.

Fits of multiple curves at the same time

By activating multiple datasets for fitting it is possible to minimize the Chi^2 error of all curves at the same time with the same set of parameters.

The parameters that can be changed for each measurement curve are the energy, angular resolution, multiplicator, translation and polarization. If the multiplicator is fitted it is used for all fitted curves. Independent fitting of the multiplicator is not possible. If multiple curves should be fitted at the same time the optical constants should not be fitted as they change for each energy. Instead it is recommed that in the tab “Optical Constants Database” the automatically setting of the optical constants from files should be activated. If the optical constants should be fitted as well use the script and script variables.

documentation/fit.1365027665.txt.gz · Last modified: 2015/09/09 08:56 (external edit)