Digital Currency Futures Double-EMA Turning Point Strategy (Tutorial-2)

    // Strategy main loop
    while (true) {
        // Obtain the K-line data for current trading pairs and contracts
        var r = _C(exchange.GetRecords)
        // Obtain the length of the K-line data, i.e. l
        var l = r.length
        // Judge the K-line length that l must be greater than the indicator period (if not, the indicator function cannot calculate valid indicator data), or it will be recycled
        if (l < Math.max(ema1Period, ema2Period)) {
            // Wait for 1,000 milliseconds, i.e. 1 second, to avoid rotating too fast
            Sleep(1000)
            // Ignore the code after the current if, and execute while loop again
            continue
        }
        
        // Calculate ema indicator data
        var ema1 = TA.EMA(r, ema1Period)
        var ema2 = TA.EMA(r, ema2Period)
        
        // Drawing chart
        $.PlotRecords(r, 'K-Line')    // Drawing the K-line chart
        // When the last BAR timestamp changes, i.e. when a new K-line BAR is created
        if(preTime !== r[l - 1].Time){
            // The last update of the last BAR before the new BAR appears
            $.PlotLine('ema1', ema1[l - 2], r[l - 2].Time)
            $.PlotLine('ema2', ema2[l - 2], r[l - 2].Time)
            
            // Draw the indicator line of the new BAR, i.e. the indicator data on the current last BAR
            $.PlotLine('ema1', ema1[l - 1], r[l - 1].Time)
            $.PlotLine('ema2', ema2[l - 1], r[l - 1].Time)
            
            // Update the timestamp used for comparison
            preTime = r[l - 1].Time
        } else {
            // When no new BARs are generated, only the indicator data of the last BAR on the chart is updated
            $.PlotLine('ema1', ema1[l - 1], r[l - 1].Time)
            $.PlotLine('ema2', ema2[l - 1], r[l - 1].Time)
        }
        
        // Conditions for opening long positions, turning points
        var up = (ema1[l - 2] > ema1[l - 3] && ema1[l - 4] > ema1[l - 3]) && (ema2[l - 2] > ema2[l - 3] && ema2[l - 4] > ema2[l - 3])
        // Conditions for opening short positions, turning points
        var down = (ema1[l - 2] < ema1[l - 3] && ema1[l - 4] < ema1[l - 3]) && (ema2[l - 2] < ema2[l - 3] && ema2[l - 4] < ema2[l - 3])
        
To be continued...