amfUtils.js
function amf3encDouble(num) {
    var buf = new Buffer(9);
    buf.writeUInt8(0x05, 0);
    buf.writeDoubleBE(num, 1);
    return buf;
}
function amf3encDouble(num) {
    var buf = new Buffer(9);
    buf.writeUInt8(0x05, 0);
    buf.writeDoubleBE(num, 1);
    return buf;
}
function amf3encDouble ( num ) { var buf = new Buffer ( 9 ) ; buf . writeUInt8 ( 0x05 , 0 ) ; buf . writeDoubleBE ( num , 1 ) ; return buf ; }
AMF3 Encode Double
@param num
@returns {Buffer}
AMF3 Encode Double