function number_format( number, decimals, dec_point, thousands_sep ) {
    // Format a number with grouped thousands
    // 
    // +    discuss at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_number_format/
    // +       version: 902.1612
    // +   original by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +     bugfix by: Michael White (http://getsprink.com)
    // +     bugfix by: Benjamin Lupton
    // +     bugfix by: Allan Jensen (http://www.winternet.no)
    // +    revised by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
    // +     bugfix by: Howard Yeend
    // +    revised by: Luke Smith (http://lucassmith.name)
    // +     bugfix by: Diogo Resende
    // +     bugfix by: Rival
    // %        note 1: For 1000.55 result with precision 1 in FF/Opera is 1,000.5, but in IE is 1,000.6
    // *     example 1: number_format(1234.56);
    // *     returns 1: '1,235'
    // *     example 2: number_format(1234.56, 2, ',', ' ');
    // *     returns 2: '1 234,56'
    // *     example 3: number_format(1234.5678, 2, '.', '');
    // *     returns 3: '1234.57'
    // *     example 4: number_format(67, 2, ',', '.');
    // *     returns 4: '67,00'
    // *     example 5: number_format(1000);
    // *     returns 5: '1,000'
    // *     example 6: number_format(67.311, 2);
    // *     returns 6: '67.31'

    var n = number, prec = decimals;
    n = !isFinite(+n) ? 0 : +n;
    prec = !isFinite(+prec) ? 0 : Math.abs(prec);
    var sep = (typeof thousands_sep == "undefined") ? ',' : thousands_sep;
    var dec = (typeof dec_point == "undefined") ? '.' : dec_point;

    var s = (prec > 0) ? n.toFixed(prec) : Math.round(n).toFixed(prec); //fix for IE parseFloat(0.55).toFixed(0) = 0;

    var abs = Math.abs(n).toFixed(prec);
    var _, i;

    if (abs >= 1000) {
        _ = abs.split(/\D/);
        i = _[0].length % 3 || 3;

        _[0] = s.slice(0,i + (n < 0)) +
              _[0].slice(i).replace(/(\d{3})/g, sep+'$1');

        s = _.join(dec);
    } else {
        s = s.replace('.', dec);
    }

    return s;
}