[Insight-users] gradientdescentoptimizer scales

[Felix Bollenbeck]

Hi all,
i want to use a gradient descent optimizer for bspline registration 
(LBFGS optimizer fails during linesearch)

vnl_lbfgs: ** EEEK **
 IFLAG= -1  LINE SEARCH FAILED.

i want to use simple gradientdescent for a start to see whats happening.

i assume that itkRegularStepGradientDescentOptimizer has scales for each 
dimension and these are max 128 large and identity.

Description: itk::ERROR: RegularStepGradientDescentOptimizer(0x8566940): 
The size of Scales is 128, but the NumberOfParameters for the 
CostFunction is 338.

which means I have to pass a larger scales vector to the optimizer?

regards,

felix.