title: "Invalid Index" error in Scilab
body: <p>I'm using the following code:</p>
  
  <pre><code>for t = linspace(0,2,500)   
  
     x(t) = 1+ t^2;   
     y(t) = 2*t;  
     r(t) = sqrt((x(t))^2+(y(t))^2);  
  
     radius = 1.6
  
     if r(t) &gt; 0.999*radius &amp; r(t) &lt; 1.001*radius then
         solucion = t;
  
     end
  end;
  
  disp(solucion, "the solution is:")
  </code></pre>
  
  <p>Which works fine with <code>t</code> > 1 and different radius values.</p>
  
  <p>But I get <code>error 21: Invalid index</code> when <code>t</code> takes values between 0 and 1.</p>
  
  <p>I need to work with those values as well. How do I handle this? </p>