title: How to print float to n decimal places including trailing 0s?
body: <p>I need to print or convert a float number to 15 decimal place string even if the result has many trailing 0s eg:</p>
  
  <p>1.6 becomes 1.6000000000000000</p>
  
  <p>I tried round(6.2,15) but it returns 6.2000000000000002 adding a rounding error</p>
  
  <p>I also saw various people online who put the float into a string and then added trailing 0's manually but that seems bad...</p>
  
  <p>What is the best way to do this?</p>