Problem.objective

t3toolbox.backend.optimizers.Problem.objective(x_cores, sample=None, data=None)

def objective(self, x_cores: Tangent, sample=None, data=None):

½‖S(x)-data‖² (+ ρ(x) if regularized) on the full data (sample=None) or an explicit minibatch; no frame sweep (cheap – for the line search / the full-batch stop signal). The reg term reads x_cores directly through geom.point_norm_sq (exact for any point; docs/contributor/fitting_internals.md §”The base point as a tangent”). sample and data go together: one without the other is a structural error (the data used to be silently ignored when only it was passed).

Parameters:

x_cores (Tangent)