[Insight-users] Optimizer and R+* Cost functions

[Julien Michel]

Dear ITK users,

I am trying to use ITK optimizers (mainly GradientDescentOptimizer) to 
optimize my own cost function. unfortunately, it is only defined on R+*, 
and the optimizer happens to end sometimes asking for negative or null 
values. I made my cost function return zero in such cases, but then the 
derivative is null (function is constant on R-) and the optimizer does 
not evolve anymore ... Is there a way to restrain the optimizer search 
domain ?

Regards,

Julien
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Julien MICHEL - Ingénieur d'études - Traitement d'images
CS Systèmes d'Information - Division ESPACE
Département Information Géographique & Image
Téléphone : +33 561 17 64 27
Email : julien.michel at c-s.fr

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