[Insight-users] LevenbergMarquardt Optimizer

[Mark Hastenteufel]

Hello!

I'm wondering about the usage of the LevenbergMarquardt algorithm for
optimization of multiple valued costfunctions. One have to implement a
gradient function, even though it is possible from vnl library to use
LevenebergMarquardt without implementing the gradient function.
Therefore one have to set
vnl_least_squares_function::UseGradient=no_gradient. But one have no
access to vnl_least_squares_function and
itkMultipleValuedVnlCostFunctionAdaptor, respectivly. The appropriate
method GetCostFunctionAdaptor (void) in
itkMultipleValuedNonLinearVnlOptimizer is declared protected. I think
this should be a public method or there should be a method like
itkMultipleValuedNonLinearVnlOptimizer->UseGradient() and
itkMultipleValuedNonLinearVnlOptimizer->UseNoGradient().

Any comments about that? Thanks in advance,


Mark

 
-- 
Mark Hastenteufel
Deutsches Krebsforschungszentrum         (German Cancer Research Center)
Div. Medical and Biological Informatics H0100    Tel: (+49) 6221-42 2353
Im Neuenheimer Feld 280                          Fax: (+49) 6221-42 2345
D-69120 Heidelberg              e-mail            M.Hastenteufel@DKFZ.de
Germany                         http://www.dkfz.de/mbi/people/markh.html