PostprocessorInterface

The PostprocessorInterface defines the methods used for retrieving PostprocessorValue references. Many objects in MOOSE support the retrieval of these references for use in calculations. Postprocessors being "post"-processors generally execute after most other systems in MOOSE so these values are often lagged when being used in another calculation.

   * Retrieve the value of a Postprocessor or one of it's old or older values
   * @param param_name The name of the Postprocessor parameter (see below)
   * @param index The index of the Postprocessor
   * @return A reference to the desired value
   *
   * The name required by this method is the name that is hard-coded into
   * your source code. For example, if you have a Kernel that requires
   * a Postprocessor you may have an input file with "pp = my_pp", this function
   * requires the "pp" name as input (see .../moose_test/functions/PostprocessorFunction.C)
   *
   * see getPostprocessorValueByName getPostprocessorValueOldByName getPostprocessorValueOlderByName
   */
  const PostprocessorValue & getPostprocessorValue(const std::string & param_name,
                                                   const unsigned int index = 0) const;
  const PostprocessorValue & getPostprocessorValueOld(const std::string & param_name,
                                                      const unsigned int index = 0) const;
  const PostprocessorValue & getPostprocessorValueOlder(const std::string & param_name,
                                                        const unsigned int index = 0) const;
(moose/framework/include/interfaces/PostprocessorInterface.h)