title: What does double store?
body: <p>I'm sending the value <code>4 *cos( fmod( acos(2.0/4.0), 2*3.14159265) )</code> as <code>double</code> to this function but I get output as</p>
  
  <pre><code>2
  1k1
  </code></pre>
  
  <p>What is wrong here?</p>
  
  <pre><code>void convert_d_to_f(double n)
  {
      cout&lt;&lt;n&lt;&lt;" ";
  
      double mantissa;
      double fractional_part;
  
      fractional_part = modf(n,&amp;mantissa);
      double x = fractional_part;
  
      cout&lt;&lt;mantissa&lt;&lt;"k"&lt;&lt;fractional_part&lt;&lt;'\n';
  }
  </code></pre>