Nodejs Utililty Methods Number Format

Number.prototype.format = function(n, x, s, c) {
  var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\D' : '$') + ')',
      num = this.toFixed(Math.max(0, ~~n));
  return (c ? num.replace('.', c) : num).replace(new RegExp(re, 'g'), '$&' + (s || ','));
};

Number.prototype.format = function(n, x, s, c) {
    var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\D' : '$') + ')'
        , num = this.toFixed(Math.max(0, ~~n));
    return (c ? num.replace('.', c) : num).replace(new RegExp(re, 'g'), '$&' + (s || ','));
};

Number.prototype.format = function(n, x, s, c) {
    if (arguments.length === 0) { n = 2; x = 3; s = ','; c = '.'; }
    var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\D' : '$') + ')',
        num = this.toFixed(Math.max(0, Math.floor(n)));
    return (c ? num.replace('.', c) : num).replace(new RegExp(re, 'g'), '$&' + (s || ','));
};

Number.prototype.format = function(n, x, unit) {
    var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\,' : '$') + ')';
    var concatunit = "";
    if (unit != null){ concatunit = " "+unit; }
    return this.toFixed(Math.max(0, ~~n)).replace(new RegExp(re, 'g'), '$&.')+concatunit;

Number.prototype.formatNum = function(n, x, s, c) {
    var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\D' : '$') + ')',
        num = this.toFixed(Math.max(0, ~~n));
    return (c ? num.replace('.', c) : num).replace(new RegExp(re, 'g'), '$&' + (s || ','));
};

Number.prototype.formatNumber = function() {
  var a = Math.abs(this).toString().split('');
  v = '';
  var n = 0;
  while (a.length > 0) {
    if (n>0 && n%3 == 0)
      v = '.' + v;
    v = a.pop() + v;
    n ++;
...

Number.prototype.formatNumber = function(c, d, t){
  var n = this,
      c = isNaN(c = Math.abs(c)) ? 2 : c,
      d = d == undefined ? "." : d,
      t = t == undefined ? "," : t,
      s = n < 0 ? "-" : "",
      i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "",
      j = (j = i.length) > 3 ? j % 3 : 0;
     return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");
...

Number.prototype.formatNumber = function(c, d, t) {
    var n = this, c = isNaN(c = Math.abs(c)) ? 2 : c, 
    d = d == undefined ? "," : d, 
    t = t == undefined ? "." : t, 
    s = n < 0 ? "-" : "", 
    i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "", 
    j = (j = i.length) > 3 ? j % 3 : 0;
    return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");

Number.THOUSAND_STEP = ",";
Number.DECIMAL_POINT = ".";
Number.prototype.format = function(thousandSep, decPoint) {
  var decimal, str;
  thousandSep = thousandSep || Number.THOUSAND_STEP;
  decPoint = decPoint || Number.DECIMAL_POINT;
  decimal = this.toString().split(".");
  str = Math.abs(this)
    .toFixed(0)
...

Number.prototype.formatAmount=function(c, d, t) {
    var n = this, 
    c = isNaN(c = Math.abs(c)) ? 2 : c, 
    d = d == undefined ? "." : d,  
    t = t == undefined ? "," : t,  
    s = n < 0 ? "-" : "", 
    i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "", 
    j = (j = i.length) > 3 ? j % 3 : 0;
    return s + "?" + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");
...