A simple radix(n) encoding function

gistfile1.js

var toRadix = (function () {
    var chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_";
    return function(N, radix) {
        var HexN = "", Q = Math.floor(Math.abs(N)), R;
        while (true) {
            R = Q % radix;
            HexN = chars.charAt(R) + HexN;
            Q = (Q - R) / radix; 
            if (Q == 0) break;
        }
        return ((N < 0) ? "-" + HexN : HexN);
    }
})();