st parameter is a string that indicates the name of the slider. It is followed by four numeric parameters. The second parameter <code>0.1</code> indicates the default value of the slider, i.e. the value that the slider will deliver when the program is started. Then we have the minimum value <code>0</code>, the maximum value <code>1</code> and the variation step <code>0.01</code>.</p>
<h3 id="example-3-exercise-add-a-frequency-control">Example 3: Exercise, add a frequency control</h3>
<p>As an exercise, repl