Add a postprocessor that computes the inner product of two variable (i…

…daholab#7532)

framework/include/postprocessors/VariableInnerProduct.h

@@ -0,0 +1,38 @@
+/****************************************************************/
+/*               DO NOT MODIFY THIS HEADER                      */
+/* MOOSE - Multiphysics Object Oriented Simulation Environment  */
+/*                                                              */
+/*           (c) 2010 Battelle Energy Alliance, LLC             */
+/*                   ALL RIGHTS RESERVED                        */
+/*                                                              */
+/*          Prepared by Battelle Energy Alliance, LLC           */
+/*            Under Contract No. DE-AC07-05ID14517              */
+/*            With the U. S. Department of Energy               */
+/*                                                              */
+/*            See COPYRIGHT for full restrictions               */
+/****************************************************************/
+
+#ifndef VARIABLEINNERPRODUCT_H
+#define VARIABLEINNERPRODUCT_H
+
+#include "ElementIntegralVariablePostprocessor.h"
+
+//Forward Declarations
+class VariableInnerProduct;
+
+template<>
+InputParameters validParams<VariableInnerProduct>();
+
+class VariableInnerProduct : public ElementIntegralVariablePostprocessor
+{
+public:
+  VariableInnerProduct(const InputParameters & parameters);
+
+protected:
+  virtual Real computeQpIntegral() override;
+
+  /// Holds the values of second_variable at current quadrature points
+  const VariableValue & _v;
+};
+
+#endif //VariableInnerProduct_H

framework/src/base/Moose.C

@@ -211,6 +211,7 @@
 #include "ElementL2Difference.h"
 #include "TimeExtremeValue.h"
 #include "RelativeSolutionDifferenceNorm.h"
+#include "VariableInnerProduct.h"
 
 // vector PPS
 #include "ConstantVectorPostprocessor.h"
@@ -624,6 +625,7 @@ registerObjects(Factory & factory)
   registerPostprocessor(ElementL2Difference);
   registerPostprocessor(TimeExtremeValue);
   registerPostprocessor(RelativeSolutionDifferenceNorm);
+  registerPostprocessor(VariableInnerProduct);
 
   // vector PPS
   registerVectorPostprocessor(ConstantVectorPostprocessor);

framework/src/postprocessors/VariableInnerProduct.C

@@ -0,0 +1,35 @@
+/****************************************************************/
+/*               DO NOT MODIFY THIS HEADER                      */
+/* MOOSE - Multiphysics Object Oriented Simulation Environment  */
+/*                                                              */
+/*           (c) 2010 Battelle Energy Alliance, LLC             */
+/*                   ALL RIGHTS RESERVED                        */
+/*                                                              */
+/*          Prepared by Battelle Energy Alliance, LLC           */
+/*            Under Contract No. DE-AC07-05ID14517              */
+/*            With the U. S. Department of Energy               */
+/*                                                              */
+/*            See COPYRIGHT for full restrictions               */
+/****************************************************************/
+
+#include "VariableInnerProduct.h"
+
+template<>
+InputParameters validParams<VariableInnerProduct>()
+{
+  InputParameters params = validParams<ElementIntegralVariablePostprocessor>();
+  params.addRequiredCoupledVar("second_variable", "The name of the second variable in the inner product (variable, second_variable)");
+  return params;
+}
+
+VariableInnerProduct::VariableInnerProduct(const InputParameters & parameters) :
+    ElementIntegralVariablePostprocessor(parameters),
+    _v(coupledValue("second_variable"))
+{
+}
+
+Real
+VariableInnerProduct::computeQpIntegral()
+{
+  return _u[_qp] * _v[_qp];
+}

test/tests/postprocessors/variable_inner_product/gold/variable_inner_product.csv

@@ -0,0 +1,4 @@
+time,f_dot_f,f_dot_g,norm_f
+0,0,0,0
+1,0.4,4.1633363423443e-17,0.63245553203368
+

test/tests/postprocessors/variable_inner_product/tests

@@ -0,0 +1,8 @@
+[Tests]
+  [./variable_inner_product_test]
+    type = 'CSVDiff'
+    input = 'variable_inner_product.i'
+    csvdiff = 'variable_inner_product.csv'
+    group = 'requirements'
+  [../]
+[]

test/tests/postprocessors/variable_inner_product/variable_inner_product.i

@@ -0,0 +1,109 @@
+[Mesh]
+  type = GeneratedMesh
+  dim = 2
+  nx = 2
+  ny = 2
+  xmin = -1
+  xmax = 1
+  ymin = 0
+  ymax = 1
+  elem_type = QUAD9
+[]
+
+[AuxVariables]
+  [./f]
+    order = SECOND
+    family = LAGRANGE
+    [./InitialCondition]
+      type = FunctionIC
+      function = leg2
+    [../]
+  [../]
+  [./g]
+    order = FIRST
+    family = LAGRANGE
+    [./InitialCondition]
+      type = FunctionIC
+      function = leg1
+    [../]
+  [../]
+[]
+
+[Variables]
+  [./u]
+    order = FIRST
+    family = LAGRANGE
+  [../]
+[]
+
+[Kernels]
+  [./diff]
+    type = Diffusion
+    variable = u
+  [../]
+[]
+
+[Functions]
+  [./leg1]
+    type = ParsedFunction
+    value = 'x'
+  [../]
+
+  [./leg2]
+    type = ParsedFunction
+    value = '0.5*(3.0*x*x-1.0)'
+  [../]
+[]
+
+[BCs]
+  active = 'left right'
+
+  [./left]
+    type = DirichletBC
+    variable = u
+    boundary = 1
+    value = 0
+  [../]
+
+  [./right]
+    type = DirichletBC
+    variable = u
+    boundary = 2
+    value = 1
+  [../]
+[]
+
+[Executioner]
+  type = Steady
+
+  # Preconditioned JFNK (default)
+  solve_type = 'PJFNK'
+
+  [./Quadrature]
+    order = fourth
+  []
+[]
+
+[Postprocessors]
+  [./f_dot_g]
+    type = VariableInnerProduct
+    variable = f
+    second_variable = g
+  [../]
+
+  [./f_dot_f]
+    type = VariableInnerProduct
+    variable = f
+    second_variable = f
+  [../]
+
+  [./norm_f]
+    type = ElementL2Norm
+    variable = f
+  [../]
+[]
+
+[Outputs]
+  file_base = variable_inner_product
+  csv = true
+[]