title: AMPL syntax error
body: <p>I'm learnig to use AMPL and I wrote the next script </p>
  
  <pre><code># Problema 2
      set P #plantas
      set PI #puntos intermedios
      set CD # centros de distribucion
      set O # origenes
      set D # destinos
  
      param coste {i in O , j in D}
      param produc {k in P}
      param capac {l in PI}
      param requiere {m in CD}
  
      var cantidad{O,D}&gt;==0;
  
      check: sum{k in P} produc[k] &lt;= sum{m in CD} requiere[m];
  
      minimize costo_transporte: sum{i in O, j in D} coste[i,j]*cantidad[i,j];
  
      subject to restriccion_produccion{k in P}:
          sum{j in D}cantidad[k,j]&lt;=produc[k];
  
      subject to restriccion_intermedio_entrada{l in PI}:
          sum{i in O}cantidad[i,l]&lt;=capac[l];
  
      subject to resctriccion_intermedio_salida{l in PI}:
          sum{i in O}cantidad[i,j] - sum{j in D}cantidad[l,j]&gt;=0;
  
      subject to restriccion_demanda{m in CD}:
          sum{i in O}cantidad[i,m]=requiere[m];
  </code></pre>
  
  <p>with the next data file</p>
  
  <pre><code>set P:= Rancagua SanPablo Bogota;
  set PI:= Lima Mendoza;
  set CD:= Santiago RiodeJaneiro Quito Caracas;
  set O:= Rancagua SanPablo Bogota Santiago Lima Mendoza;
  set D:= Santiago RiodeJaneiro Quito Caracas Lima Mendoza;
  
  param coste:
              Santiago RiodeJaneiro Quito Caracas Lima Mendoza:=
  Rancagua        3       20      30      30      10      6
  SanPablo        15      5       35      40      20      12
  Bogota          45      25      10      12      25      30
  Santiago        0       15      30      48      12      10
  Lima            12      22      8       30      0       15
  Mendoza         10      15      12      35      15      0;
  
  param produc:=
  Rancagua    300
  SanPablo    250
  Bogota      200;
  
  param capac:=
  Lima    150
  Mendoza 180;
  
  param requiere:=
  Santiago        120
  RiodeJaneiro    300
  Quito           80
  Caracas         200;
  </code></pre>
  
  <p>But when I charge the mod file, AMPL print </p>
  
  <blockquote>
    <p>ampl: model 'C:\Users\Laura\Desktop\Monserrat\P2\problema2.mod';</p>
    
    <p>C:\Users\Laura\Desktop\Monserrat\P2\problema2.mod, line 3 (offset 30):
        syntax error</p>
  </blockquote>
  
  <p>I reviewed the code, but I don't understand what is the error.
  Please! Help me.</p>