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JavaScript: Get the second digit from a number?

I have a number assigned to a variable, like that:

var myVar = 1234;

Now I want to get the second digit (2 in this case) from that number without converting it to a string first. Is that possible?

Solution

  • So you want to get the second digit from the decimal writing of a number.

    The simplest and most logical solution is to convert it to a string : 

    var digit = (''+myVar)[1];

    or 

    var digit = myVar.toString()[1];

    If you don't want to do it the easy way, or if you want a more efficient solution, you can do that :

    var l = Math.pow(10, Math.floor(Math.log(myVar)/Math.log(10))-1);
var b = Math.floor(myVar/l);
var digit = b-Math.floor(b/10)*10;

    Demonstration

    For people interested in performances, I made a jsperf. For random numbers using the log as I do is by far the fastest solution.