PointValueSampler

Sample a variable at specific points.

note

If the point value sampler is used with a discontinuous variable on the edge/face of a 2D/3D element, then the value from the element with the lowest ID will be returned.

The CSV output, with rows for each sampled point, contains the columns listed below. The vectors declared by PointValueSampler share the same names as the column headers.

the id of the elements containing the sampled points, with the convention mentioned above
the values of the variable(s) requested
the x, y and z coordinates of the requested sampled points

note:General sampling

The PointValueSampler samples variables at the specified points. For more flexible sampling, use the PositionsFunctorValueSampler.

Example input syntax

In this example, the variables u and v are sampled at three points, (0.1 0.1 0), (0.23 0.4 0) and (0.78 0.2 0) using a PointValueSampler.

[VectorPostprocessors]
  [./point_sample]
    type = PointValueSampler
    variable = 'u v'
    points = '0.1 0.1 0  0.23 0.4 0  0.78 0.2 0'
    sort_by = x
  [../]
[]

Input Parameters

pointsThe points where you want to evaluate the variables
C++ Type:std::vector<libMesh::Point>
Unit:(no unit assumed)
Controllable:No
Description:The points where you want to evaluate the variables
sort_byWhat to sort the samples by
C++ Type:MooseEnum
Unit:(no unit assumed)
Options:x, y, z, id
Controllable:No
Description:What to sort the samples by
variableThe names of the variables that this VectorPostprocessor operates on
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:The names of the variables that this VectorPostprocessor operates on

Required Parameters

_auto_broadcastFalse
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
contains_complete_historyFalseSet this flag to indicate that the values in all vectors declared by this VPP represent a time history (e.g. with each invocation, new values are added and old values are never removed). This changes the output so that only a single file is output and updated with each invocation
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Set this flag to indicate that the values in all vectors declared by this VPP represent a time history (e.g. with each invocation, new values are added and old values are never removed). This changes the output so that only a single file is output and updated with each invocation
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
Unit:(no unit assumed)
Options:NONE, INITIAL, LINEAR, NONLINEAR_CONVERGENCE, NONLINEAR, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM
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.
parallel_typeREPLICATEDSet how the data is represented within the VectorPostprocessor (VPP); 'distributed' indicates that data within the VPP is distributed and no auto communication is performed, this setting will result in parallel output within the CSV output; 'replicated' indicates that the data within the VPP is correct on processor 0, the data will automatically be broadcast to all processors unless the '_auto_broadcast' param is set to false within the validParams function.
Default:REPLICATED
C++ Type:MooseEnum
Unit:(no unit assumed)
Options:DISTRIBUTED, REPLICATED
Controllable:No
Description:Set how the data is represented within the VectorPostprocessor (VPP); 'distributed' indicates that data within the VPP is distributed and no auto communication is performed, this setting will result in parallel output within the CSV output; 'replicated' indicates that the data within the VPP is correct on processor 0, the data will automatically be broadcast to all processors unless the '_auto_broadcast' param is set to false within the validParams function.
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.
scaling1The postprocessor that the variables are multiplied with
Default:1
C++ Type:PostprocessorName
Unit:(no unit assumed)
Controllable:No
Description:The postprocessor that the variables are multiplied with
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
Unit:(no unit assumed)
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.
warn_discontinuous_face_valuesTrueWhether to return a warning if a discontinuous variable is sampled on a face
Default:True
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Whether to return a warning if a discontinuous variable is sampled on a face

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
Unit:(no unit assumed)
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).
control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Unit:(no unit assumed)
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
Unit:(no unit assumed)
Controllable:Yes
Description:Set the enabled status of the MooseObject.
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
Unit:(no unit assumed)
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 POSTAUX
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Forces the UserObject to be executed in POSTAUX
force_preauxFalseForces the UserObject to be executed in PREAUX
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Forces the UserObject to be executed in PREAUX
force_preicFalseForces the UserObject to be executed in PREIC during initial setup
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Forces the UserObject to be executed in PREIC during initial setup
outputsVector of output names where you would like to restrict the output of variables(s) associated with this object
C++ Type:std::vector<OutputName>
Unit:(no unit assumed)
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
Unit:(no unit assumed)
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

(moose/test/tests/vectorpostprocessors/point_value_sampler/point_value_sampler.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 10
  ny = 10
[]

[Variables]
  [./u]
  [../]
  [./v]
  [../]
[]

[Kernels]
  [./diff]
    type = Diffusion
    variable = u
  [../]
  [./diff_v]
    type = Diffusion
    variable = v
  [../]
[]

[BCs]
  [./left]
    type = DirichletBC
    variable = u
    boundary = left
    value = 0
  [../]
  [./right]
    type = DirichletBC
    variable = u
    boundary = right
    value = 1
  [../]
  [./left_v]
    type = DirichletBC
    variable = v
    boundary = left
    value = 1
  [../]
  [./right_v]
    type = DirichletBC
    variable = v
    boundary = right
    value = 0
  [../]
[]

[VectorPostprocessors]
  [./point_sample]
    type = PointValueSampler
    variable = 'u v'
    points = '0.1 0.1 0  0.23 0.4 0  0.78 0.2 0'
    sort_by = x
  [../]
[]

[Executioner]
  type = Steady
  solve_type = PJFNK
  petsc_options_iname = '-pc_type -pc_hypre_type'
  petsc_options_value = 'hypre boomeramg'
[]

[Outputs]
  execute_on = 'timestep_end'
  csv = true
[]

Example input syntax
Input Parameters