"The remainder"

"The remainder" refers to everything that is neither PDEs nor 0D problems, such as the computation of physical properties or the update of variables (e.g. $c\sim f(\mu)$ in the grand potential formulation of phase-field model).

The SLOTH development team recommends using Property_problem. This is a template class instantiated with three template parameters: first, an PROPERTY object, second, the Variables object (see VARSin the example), and third, the Postprocessing object (see PST in the example).

Alias declaration for Property_problem class template

using PropertyProblem = PropertyProblem<PROPERTY, VARS, PST>;

The users are referred to dedicated pages of the user manual for details about Variables and PostProcessing.

The PROPERTY object in Property_problem corresponds to a C++ object that inherits from the template class PropertyBase, only defined with a set of Parameter (within a Parameters object).

Similar to other types of problems, Property_problem take auxiliary Variables as inputs, and primary Variables as outputs.

Defintion of a fictitious Property_problem

auto property_params = FictitiousProperty(property_params);
using PropertyProblem = PropertyProblem<FictitiousProperty, VARS, PST>;

PropertyProblem prop_pb = fictitious_property_problem(
  "Property problem", property_params, outputs_property_var, inputs_property_var);