title: Expressing an OR constraint in linear programming
body: <p>I have a floating-point variable <code>x</code> in a linear program which shall be either <code>0</code> or between two constants <code>CONSTANT_A</code> and <code>CONSTANT_B</code>:</p>
  
  <p><code>LP.addConstraint(x == 0 OR CONSTANT_A &lt;= x &lt;= CONSTANT_B)</code></p>
  
  <p>Of course there is no such thing as an explicit <code>OR</code> in linear programming. Is there a way to express this constraint?</p>