function number_format (number, decimals, dec_point, thousands_sep) {
    var n = number, prec = decimals;
 
    var toFixedFix = function (n,prec) {
        var k = Math.pow(10,prec);
        return (Math.round(n*k)/k).toString();
    };
 
    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) ? toFixedFix(n, prec) : toFixedFix(Math.round(n), prec); //fix for IE parseFloat(0.55).toFixed(0) = 0;
 
    var abs = toFixedFix(Math.abs(n), 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);
    }
 
    var decPos = s.indexOf(dec);
    if (prec >= 1 && decPos !== -1 && (s.length-decPos-1) < prec) {
        s += new Array(prec-(s.length-decPos-1)).join(0)+'0';
    }
    else if (prec >= 1 && decPos === -1) {
        s += dec+new Array(prec).join(0)+'0';
    }
    return s;
}

function str_replace (search, replace, subject, count) {
    var i = 0, j = 0, temp = '', repl = '', sl = 0, fl = 0,
            f = [].concat(search),
            r = [].concat(replace),
            s = subject,
            ra = r instanceof Array, sa = s instanceof Array;
    s = [].concat(s);
    if (count) {
        this.window[count] = 0;
    }
 
    for (i=0, sl=s.length; i < sl; i++) {
        if (s[i] === '') {
            continue;
        }
        for (j=0, fl=f.length; j < fl; j++) {
            temp = s[i]+'';
            repl = ra ? (r[j] !== undefined ? r[j] : '') : r[0];
            s[i] = (temp).split(f[j]).join(repl);
            if (count && s[i] !== temp) {
                this.window[count] += (temp.length-s[i].length)/f[j].length;}
        }
    }
    return sa ? s : s[0];
}

function strpos (haystack, needle, offset) {
    var i = (haystack+'').indexOf(needle, (offset ? offset : 0));
    return i === -1 ? false : i;
}

function substr (f_string, f_start, f_length) {
    f_string += '';
 
    if (f_start < 0) {
        f_start += f_string.length;
    }
 
    if (f_length == undefined) {
        f_length = f_string.length;
    } else if (f_length < 0){
        f_length += f_string.length;
    } else {
        f_length += f_start;
    }
 
    if (f_length < f_start) {
        f_length = f_start;
    }
 
    return f_string.substring(f_start, f_length);
}
