title: how to convert translate()[0] to d3 v4
body: <p>I'm trying to convert following code to d3 v4</p>
  
  <pre><code>let x = this.d3Zoom.translate()[0] - this.d3xScale(this.minHz) + this.d3xScale.range()[0];
  this.d3Zoom.translate([x, 0]);
  </code></pre>
  
  <p>How do you perform translate()[0] in d3 v4?</p>