/*backtest
start: 2020-09-01 09:00:00
end: 2021-08-31 15:00:00
period: 1d
basePeriod: 1d
exchanges: [{"eid":"Futures_XTP","currency":"STOCK","minFee":0},{"eid":"Futures_XTP","currency":"STOCK","minFee":0}]
*/
// 全局变量
var level_a2h = null
var level_h2a = null