Time conversion confusion [Answered]RSS

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  warrenkc2

  Member

  25 Points

  181 Posts

  Time conversion confusion

  Mar 23, 2020 04:15 AM|warrenkc2|LINK

  If I convert 1025.1 to the format hh:mm:ss,ms there seems to be a weird issue.  The output is: 00:00:01,25.09999999999991

  https://jsfiddle.net/warrenkc/wujLk5ap/1/

  The output should be:  something like: 00:00:01,25.099

  Thank you for your help.

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  Yang Shen

  Contributor

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  916 Posts

  Re: Time conversion confusion

  Mar 23, 2020 06:01 AM|Yang Shen|LINK

  Hi warrenkc2,

  warrenkc2

  The output should be:  something like: 00:00:01,25.099

  I don't think it shall output 00:00:01,25.099, according to your code:

  function formatMilliseconds(milliseconds) {
      var seconds = Math.floor(milliseconds / 1000) % 60;
      var minutes = Math.floor(seconds / 60)  % 60;
      var hours = Math.floor(minutes / 60);
      var milliseconds = milliseconds % 1000;
  
      return pad(hours) + ':' + pad(minutes) + ':' + pad(seconds) + ',' + pad(milliseconds);
  }

  In general math, the milliseconds should be 25.1 after milliseconds % 1000, so the final output should be 00:00:01,25.1 or if you prefer 00:00:01,25.100.

  To achieve this, you will need the toFixed() method.

  Update your code to:

  var milliseconds = (milliseconds % 1000).toFixed(1);

  or toFixed(3), choose whichever you like.

  You can find more information about why it returns the wrong value at Is floating point math broken?

  Best Regard,

  Yang Shen

• • Reply
  warrenkc2

  Member

  25 Points

  181 Posts

  Re: Time conversion confusion

  Mar 23, 2020 09:18 AM|warrenkc2|LINK

  I made a new function. 

  function formatSeconds(totalSeconds) {
    var hours = Math.floor(totalSeconds / 3600);
    totalSeconds %= 3600;
    var minutes = Math.floor(totalSeconds / 60);
    var seconds = Math.floor(totalSeconds) % 60;
    var milliseconds = Math.floor(totalSeconds * 1000) % 1000;
  
    return pad(hours) + ':' + pad(minutes) + ':' + pad(seconds) + ',' + pad(milliseconds);
  }