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documentation:fit [2012/04/20 19:41]
142.103.140.43
documentation:fit [2015/09/09 08:56]
macke
Line 1: Line 1:
 +== Defined fit variables for compound mode ==
 +
 +^ 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 |
 +
 +== Defined fit variables for additional magnetization profile in compound mode ==
 +| 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 |
 +
 +
 +== Defined fit variables for element mode ==
 +^ elemental Variable ​         ^ initial lower boundary ^ Initial upper boundary ​ ^
 +| thickness ​        | 0.8*thickness ​         | 1.2*thickness |
 +| f1             | ?   | ? |
 +| f2              | ?   | ? |
 +| sigma             | 0.   |20 |
 +| f1m            | 0.   | 0. |
 +| f2m             | 0.    | 0. |
 +
 +== General fit variables ==
 +^ Variable ​         ^ initial lower boundary ^ Initial upper boundary ​ ^
 +| angular resolution| 0.    | 0.1 |
 +| measurement multiplicator | 0.1*multiplicator ​   | 10*multiplicator |
 +| qz translation | -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.txt ยท Last modified: 2015/09/09 08:56 by macke