title: Error when defining a complex number variable
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/6418807/how-to-work-with-complex-numbers-in-c">How to work with complex numbers in C?</a>  </p>
  </blockquote>
  
  
  
  <p>So I have this piece of C code that compiles with errors saying that 'complex' does not name a type:</p>
  
  <pre><code>#include &lt;stdio.h&gt;
  #include &lt;complex.h&gt;
  #include &lt;math.h&gt;
  
  int main ()
  {
      int B=9;
      double theta;
  
      double complex w;
      float x,y;
  
      x= 5*cos (theta) - 2;
      y= 5*sin (theta);
  
  
      double complex z=x+y*I;
      w=z+(B/z);
  
      for(theta=0;theta&lt;=360;theta=+30)
      { printf ("%.2f  %.2f  %.2f  %.2f",creal(z), cimag(z),y,creal(w), cimag(w));
          printf ("/n");
      } 
  
      return 0;
  
      system ("pause");
  }
  </code></pre>
  
  <p>I already include the <code>&lt;complex.h&gt;</code> so why is there still an error for the 'complex'. There are also other errors, but let just focus on this one first.</p>