You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: get.m
    path of file: ./repos/bnt/SLP/learning/@jtree_inf_engine2
    
    the code of the file until where you have to start completion: % ===
% get
% ===
%
% Description :
% -------------
%
% Reading method for the class' attributes. 
% 
% Syntax :
% --------

    
function [ val ] = get( engine, attribute_name )

val = [];

% Processing 
val = get( engine.inf_engine, attribute_name );

% Processing    
arg = upper( attribute_name );

switch arg      
 case upper( 'evidence' )
  val = engine.evidence;
 case upper( 'jtree' )
  val = engine.jtree;
 case upper( 'cliques' )
  val = engine.cliques;
  case upper( 'separator' )
  val = engine.separator;
  case upper( 'cliques_bitv' )
  val = engine.cliques_bitv;
  case upper( 'clique_weight' )
  val = engine.clique_weight;
  case upper( 'clpot' )
  val = engine.clpot;
  case upper( 'clq_ass_to_node' )
  val = engine.clq_ass_to_node;
 case upper( 'root_clq' )
  val = engine.root_clq;
  case upper( 'preorder' )
  val = engine.preorder;
  case upper( 'postorder' )
  val = engine.postorder;
  case upper( 'preorder_children' )
  val = engine.preorder_children;
  case upper( 'postorder_parents' )
  val = engine.postorder_parents;
  case upper( 'maximize' )
  val = engine.maximize;
  case upper( 'evidence' )
  val = engine.evidence;
             
 otherwise
  %   warning_str = [ 'inf_engine - get : attribute ' ...
  % 		  arg ' doesn''t exist' ];
  
  %   warning( warning_str );
end