[Insight-users] Question about levenberg-marguardt optimizationfor the normalized correlation metric

[Luis Ibanez]

Hi Zhaoqiang:


Single   valued cost function = a function that returns a single value
Multiple valued cost function = a function that returns multiple values

The Doxygen documentation states:

http://www.itk.org/Insight/Doxygen/html/classitk_1_1SingleValuedCostFunction.html
"This class is a base for the CostFunctions returning a single value"


http://www.itk.org/Insight/Doxygen/html/classitk_1_1MultipleValuedCostFunction.html
"This class is a base for the CostFunctions returning a multiple values"


For example


       sin(x)       is a single valued cost function

       exp(i.X)     is a multiple valued cost function
                    since the returned complex number
                    can be seen as an array of length = 2



For a mathematical definition:

     http://mathworld.wolfram.com/Single-ValuedFunction.html

     http://mathworld.wolfram.com/Multiple-ValuedFunction.html




   Regards,



      Luis


----------------------
Zhaoqiang Bi wrote:
> Hi Luis,
> 
> Thank you for the reply to my question. First of all, can you clarify
> the definition of single valued cost function and multiple valued cost
> function since I cannot find the definition from itk document.
> 
> Thanks.
> 
> Zhaoqiang
> 
>