title: How To write a query for testing the following code that written with eplex Lib in ECLiPSe-CLP
body: <p>I am new in ECLiPSe and have a follwing problem.
  when I write and compile this simple program:</p>
  
  <pre><code>---------------------------------
  :- lib(eplex).
  
  main1(Cost, Vars) :-
  Vars = [A1, A2, A3, B1, B2, B3, C1, C2, C3, D1, D2, D3],
  Vars :: 0.0..inf,            % variables
  A1 + A2 + A3 $= 200,            % demand constraints
  B1 + B2 + B3 $= 400,
  C1 + C2 + C3 $= 300,
  D1 + D2 + D3 $= 100,
  
  A1 + B1 + C1 + D1 $=&lt; 500,        % capacity constraints
  A2 + B2 + C2 + D2 $=&lt; 300,
  A3 + B3 + C3 + D3 $=&lt; 400,
  
  optimize(min(                % solve
  10*A1 + 7*A2 + 11*A3 +
  8*B1 + 5*B2 + 10*B3 +
  5*C1 + 5*C2 +  8*C3 +
  9*D1 + 3*D2 +  7*D3), Cost).
  ------------------------------
  </code></pre>
  
  <p>I dont know how to test it? or what is simple query for test it?</p>
  
  <p>I will be very glad ,If you guide me .
  Thanks in Advance</p>