.. _method-rol-gradient_tolerance: """""""""""""""""" gradient_tolerance """""""""""""""""" Stopping critiera based on L2 norm of gradient .. toctree:: :hidden: :maxdepth: 1 **Specification** - *Alias:* None - *Arguments:* REAL - *Default:* 1.e-4 **Description** The ``gradient_tolerance`` control defines the threshold value on the L2 norm of the objective function gradient (for unconstrained minimum or no active constraints) or the Lagrangian gradient (for constrained minimum) that indicates convergence to a stationary point. The ``gradient_tolerance`` control is currently defined only for the OPT++ and ROL libraries.