- boundaryThe list of boundary IDs from the mesh where this object appliesC++ Type:std::vector<BoundaryName> Controllable:No Description:The list of boundary IDs from the mesh where this object applies 
- variableThe name of the variable on the primary side of the interfaceC++ Type:std::vector<VariableName> Unit:(no unit assumed) Controllable:No Description:The name of the variable on the primary side of the interface 
InterfaceIntegralVariableValuePostprocessor
IMPORTANT NOTE * Any derived class of InterfaceUserObject does not support yet getMaterialProperty, please use auxvariables *
Description !syntax description /Postprocessors/InterfaceIntegralVariableValuePostprocessor
This post-processor is used to compute an integral value of variable on an interface. The type of average to compute is selected by changing the interface_value_type parameter. If the parameter interface_value_type is omitted it defaults to compute the average value between the two input variables across the interface. The various types of averages that can be computed are describe in more details in  InterfaceValueTools.
Example Input File Syntax
listing test/tests/postprocessors/interface_value/interface_integral_variable_value_postprocessor.i block=Postprocessors/diffusivity_average
Input Parameters
- interface_value_typeaverageType of value we want to computeDefault:average C++ Type:MooseEnum Controllable:No Description:Type of value we want to compute 
- neighbor_variableThe name of the variable on the secondary side of the interface. By default the primary side variable name is used for the secondary side as wellC++ Type:std::vector<VariableName> Unit:(no unit assumed) Controllable:No Description:The name of the variable on the secondary side of the interface. By default the primary side variable name is used for the secondary side as well 
Optional Parameters
- allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).Default:False C++ Type:bool Controllable:No Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable). 
- execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.Default:TIMESTEP_END C++ Type:ExecFlagEnum Controllable:No Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html. 
- execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.Default:0 C++ Type:int Controllable:No Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group. 
- force_postauxFalseForces the UserObject to be executed in POSTAUXDefault:False C++ Type:bool Controllable:No Description:Forces the UserObject to be executed in POSTAUX 
- force_preauxFalseForces the UserObject to be executed in PREAUXDefault:False C++ Type:bool Controllable:No Description:Forces the UserObject to be executed in PREAUX 
- force_preicFalseForces the UserObject to be executed in PREIC during initial setupDefault:False C++ Type:bool Controllable:No Description:Forces the UserObject to be executed in PREIC during initial setup 
Execution Scheduling Parameters
- control_tagsAdds user-defined labels for accessing object parameters via control logic.C++ Type:std::vector<std::string> Controllable:No Description:Adds user-defined labels for accessing object parameters via control logic. 
- enableTrueSet the enabled status of the MooseObject.Default:True C++ Type:bool Controllable:Yes Description:Set the enabled status of the MooseObject. 
- implicitTrueDetermines whether this object is calculated using an implicit or explicit formDefault:True C++ Type:bool Controllable:No Description:Determines whether this object is calculated using an implicit or explicit form 
- outputsVector of output names where you would like to restrict the output of variables(s) associated with this objectC++ Type:std::vector<OutputName> Controllable:No Description:Vector of output names where you would like to restrict the output of variables(s) associated with this object 
- use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.Default:False C++ Type:bool Controllable:No Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used. 
Advanced Parameters
- prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.C++ Type:MaterialPropertyName Unit:(no unit assumed) Controllable:No Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character. 
- use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.Default:False C++ Type:bool Controllable:No Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.