Nodejs Utililty Methods Number Format

Number.prototype.format = function() {
  var n = this, decPlaces = 2, decSeparator = ".", thouSeparator = ",", sign = n < 0 ? "-" : "", i = parseInt( n = Math.abs(+n || 0).toFixed(decPlaces)) + "", j = ( j = i.length) > 3 ? j % 3 : 0;
  return sign + ( j ? i.substr(0, j) + thouSeparator : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thouSeparator) + ( decPlaces ? decSeparator + Math.abs(n - i).toFixed(decPlaces).slice(2) : "");
};
function isNumber(n) {
  return !isNaN(parseFloat(n)) && isFinite(n);
var dayNames = new Array("Duminica", "Luni", "Marti", "Miercuri", "Joi", "Vineri", "Sambata");
var monthNames = new Array("Ianuarie", "Februarie", "Martie", "Aprilie", "Mai", "Iunie", "Iulie", "August", "Septembrie", "Octobmrie", "Noiembrie", "Decembrie");
...

Number.prototype.format=function(decimalPoints,thousandsSep,decimalSep){
  var val=this+'',re=/^(-?)(\d+)/,x,y;
  if (decimalPoints!=null) val = this.toFixed(decimalPoints);
  if (thousandsSep && (x=re.exec(val))){
    for (var a=x[2].split(''),i=a.length-3;i>0;i-=3) a.splice(i,0,thousandsSep);
    val=val.replace(re,x[1]+a.join(''));
  if (decimalSep) val=val.replace(/\./,decimalSep);
  return val;
...

Number.prototype.format = function(digit, separator)
    if (typeof digit != 'number' || digit > 99) 
        throw new Error('Number.toFormattedString - Wrong argument.');
    var decimals = Math.round(((this - Math.floor(this)) * Math.pow(10, digit))).toString();
    while (digit - decimals.length > 0) 
        decimals = '0' + decimals;
    if (typeof separator != 'string' || separator.length != 1) 
        separator = '.';
    return Math.floor(this).toString() + separator + decimals.substr(0, digit);
};

Number.prototype.format = function (fmt) {
    var s = this.toFixed(2).toString();
    var decimals = "";
    if (s.indexOf(".") > 0) {
        var arr = s.split('.');
        s = arr[0]; decimals = arr[1];
    if (this > 0 && this < 1000) {
        if (decimals != "" && parseInt(decimals) != 0) {
...

Number.decPoint = ',';
Number.thousand_sep = '.';
Number.prototype.format = function (k, fixLength) {
    if (!k) k = 0;
    var neu = '';
    var sign = this < 0 ? '-' : '';
    var f = Math.pow(10, k);
    var zahl = Math.abs(this);
    zahl = '' + parseInt(zahl * f + .5) / f;
...

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

Number.prototype.format = function(n, x) {
    var re = '(\\d)(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\.' : '$') + ')';
    return this.toFixed(Math.max(0, ~~n)).replace(new RegExp(re, 'g'), '$1,');
};

Number.prototype.format = function (n, x) {
    var re = '\\d(?=(\\d{' + (x || 3) + '})+' + (n > 0 ? '\\.' : '$') + ')';
    return this.toFixed(Math.max(0, ~~n));
};

Number.isInteger = Number.isInteger || function(value) {
  return typeof value === 'number' && 
    isFinite(value) && 
    Math.floor(value) === value;
};
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 || ','));
};