function number_format (number, decimals, dec_point, thousands_sep) {
        var exponent = "";
        var numberstr = number.toString ();
        var eindex = numberstr.indexOf ("e");
        if (eindex > -1) {
                exponent = numberstr.substring (eindex);
                number = parseFloat (numberstr.substring (0, eindex));
        }
 
        if (decimals != null) {
                var temp = Math.pow (10, decimals);
                number = Math.round (number * temp) / temp;
        }
        var sign = number < 0 ? "-" : "";
        var integer = (number > 0 ? 
 
        Math.floor (number) : Math.abs (Math.ceil (number))).toString ();
 
        var fractional = number.toString ().substring (integer.length + sign.length);
        dec_point = dec_point != null ? dec_point : ".";
        fractional = decimals != null  && decimals > 0 || fractional.length > 1 ? (dec_point + fractional.substring (1)) : "";
        if (decimals != null && decimals > 0) {
                for (i = fractional.length - 1, z = decimals; i < z; ++i) {
                        fractional += "0";
                }
        }
 
        thousands_sep = (thousands_sep != dec_point || fractional.length == 0) ? thousands_sep : null;
        if (thousands_sep != null &&  thousands_sep != "") {
                for (i = integer.length - 3; i > 0; i -= 3){
                        integer = integer.substring (0 , i) + thousands_sep + integer.substring (i);
                }
        }  
        return sign + integer + fractional + exponent;
}