title: How to clear ng-select selection
body: <p>Is it possible to programmatically clear the selection of an ng-select dropdown? I'm wanting the equivalent behaviour of clicking the clear icon, but triggered programmatically.</p>
  
  <p><a href="https://i.stack.imgur.com/q7w1Z.png" rel="noreferrer"><img src="https://i.stack.imgur.com/q7w1Z.png" alt="Screenshot of ng-select dropdown, with clear icon circled in red"></a></p>
  
  <p>I was expecting a <code>clear()</code> method or something similar, but the <a href="https://github.com/ng-select/ng-select#methods" rel="noreferrer">documented API</a> doesn't have anything along those lines.</p>
  
  <p>This is my dropdown code:</p>
  
  <pre><code>&lt;ng-select class="ng-select-wrap"
             [searchFn]="multiTermSearch"
             [items]="calculationOptions"
             placeholder="Please select..."
             name="calculation"
             #calculationValue="ngModel"
             [(ngModel)]="selectedCalculation"&gt;
  &lt;/ng-select&gt;
  
  </code></pre>