LBFGSPrms
The LBFGSPrms
class is used to group together all parameters that control the L-BFGS optimization process.
Value parameters
- delta
-
delta for convergence test. Determines the minimum rate of decrease of the objective function. The optimization stops iterations when the following condition is met: (f'-f)/f < delta. In the formula, f' is the objective value of
past
iterations ago, and f is the objective value of the current iteration. The default value is 1e-5. - epsilon
-
epsilon for convergence test. Determines the accuracy with which the solution is to be found. A minimization terminates when: ||g|| <
epsilon
* max(1, ||x||). In the formula, ||.|| denotes the Euclidean L2-norm. The default value is 1e-5. - lineSearch
-
LBFGSLineSearchAlg
to specify what line search algorithm should be used. The default value isLBFGSLineSearchAlg.Default
. - lineSearchPrms
-
BFGSLineSearchPrms
to specify the parameters needed during the execution of the line search algorithm routine. - m
-
number of past iterations stored in memory to approximate the inverse Hessian matrix of the current iteration. Values less than 3 are not recommended. Large values will result in excessive computing time. The default value is 6.
- maxIterations
-
the maximum number of iterations. The
lbfgsMain
andlbfgsMainCWrapper
methods inWrapper
terminate an optimization process with theLBFGSReturnCode.MaximumIteration
return code when the iteration count exceeds this parameter. Setting this parameter to zero continues the optimization process until a convergence or error. The default value is 0. - orthantWise
-
Option
of typeOrthantWisePrms
that specifies whether the Orthant-Wise Limited-memory Quasi-Newton (OWL-QN) optimization method should be used when calculating the value to be optimized. If this parameter is set toSome
, then thelineSearch
parameter should always be set toLBFGSLineSearchAlg.BacktrackingOrthantWise
or the optimization will terminate with the return codeLBFGSReturnCode.InvalidLineSearch
. The same will occur when thelineSearch
parameter is set toLBFGSLineSearchAlg.BacktrackingOrthantWise
and this parameter is set toNone
. - past
-
distance for delta-based convergence test. Determines how many iterations to compute the rate of decrease of the objective function. A value of zero implies the delta-based convergence test will not be performed. The default value is 0.
Attributes
- Graph
-
- Supertypes
-
trait Serializabletrait Producttrait Equalsclass Objecttrait Matchableclass Any