title: How do I find values close to a given value?
body: <p>I have <code>data  = [1 1.2 1.3 1.5 1.8]</code></p>
  
  <p>I want to find closest values before and after from data for this point, <code>b = 1.23</code></p>
  
  <p>How do I do this?</p>