title: Numpy Arange generating values of inconsistent decimal points
body: <p>Can someone explain me what's happening here? </p>
  
  <p>Why is there more decimal points for 0.3 and 0.7 values. 
  I just want 1 decimal point values.</p>
  
  <pre class="lang-py prettyprint-override"><code>threshold_range = np.arange(0.1,1,0.1)
  threshold_range.tolist()
  </code></pre>
  
  <pre><code>[Output]: [0.1, 0.2, 0.30000000000000004, 0.4, 0.5, 0.6, 0.7000000000000001, 0.8, 0.9]
  </code></pre>