How to create a function that converts a Number to a Bijective Hexavigesimal?

Maybe i am just not that good enough in math, but I am having a problem in converting a number into pure alphabetical Bijective Hexavigesimal just like how Microsoft Excel/OpenOffice Calc do it.

Here is a version of my code but did not give me the output i needed:

    var toHexvg = function(a){
     var x='';
     var let="_abcdefghijklmnopqrstuvwxyz";
     var len=let.length;
     var b=a;
     var cnt=0;
     var y = Array();
     do{
      a=(a-(a%len))/len;
      cnt++;
     }while(a!=0)
     a=b;
     var vnt=0;
     do{
      b+=Math.pow((len),vnt)*Math.floor(a/Math.pow((len),vnt+1));
      vnt++;
     }while(vnt!=cnt)
     var c=b;
     do{
      y.unshift( c%len );
      c=(c-(c%len))/len;
     }while(c!=0)
     for(var i in y)x+=let[y[i]];
     return x;
    }

The best output of my efforts can get is: a b c d ... y z ba bb bc – though not the actual code above. The intended output is suppose to be a b c ... y z aa ab ac ... zz aaa aab aac ... zzzzz aaaaaa aaaaab, you get the picture.

Basically, my problem is more on doing the ”math” rather than the function. Ultimately my question is: How to do the Math in Hexavigesimal conversion, till a [supposed] infinity, just like Microsoft Excel.

And if possible, a source code, thank you in advance.

Answer

Okay, here’s my attempt, assuming you want the sequence to be start with “a” (representing 0) and going:

a, b, c, ..., y, z, aa, ab, ac, ..., zy, zz, aaa, aab, ...

This works and hopefully makes some sense. The funky line is there because it mathematically makes more sense for 0 to be represented by the empty string and then “a” would be 1, etc.

alpha = "abcdefghijklmnopqrstuvwxyz";

function hex(a) {
  // First figure out how many digits there are.
  a += 1; // This line is funky
  c = 0;
  var x = 1;      
  while (a >= x) {
    c++;
    a -= x;
    x *= 26;
  }

  // Now you can do normal base conversion.
  var s = "";
  for (var i = 0; i < c; i++) {
    s = alpha.charAt(a % 26) + s;
    a = Math.floor(a/26);
  }

  return s;
}

However, if you’re planning to simply print them out in order, there are far more efficient methods. For example, using recursion and/or prefixes and stuff.