The attached indicator leads the crash

[takeo]

[NinjaTrader Version]
6.5.1000.14

[Brief summary of the problem encounterd]
I am learning Ninja script and trying to use the update() method in a indicator. I have successfully compiled it but the application was clashed when I applied it to a chart.

[Discribe in steps how to reproduce this issue]
1. Create a daily chart.
2. Add the attached indicator to the chart.

        protected override void Initialize()
        {
            Add(new Plot(Color.FromKnownColor(KnownColor.Blue), PlotStyle.Dot, "trade"));
            Add(new Plot(Color.FromKnownColor(KnownColor.Blue), PlotStyle.Dot, "position"));   
            CalculateOnBarClose = false;
            Overlay    = true;
            PriceTypeSupported = true;
   PaintPriceMarkers = false;
   HorizontalGridLines = false;
   VerticalGridLines = false;
        }
        /// <summary>
        /// Called on each bar update event (incoming tick)
        /// </summary>
        protected override void OnBarUpdate()
        {
 
   if (CurrentBar < 50 )
    return;
 
   if(FirstTickOfBar)
   {
     Plot0.Set(Plot0[1]);        
     Plot1.Set(0);    
             // Condition set 1
             if (Plot0[0] <= 0 && Close[0] > EMA(50)[0]
                 && CrossAbove(MACD(fast, slow, smooth).Avg, MACD(fast, slow, smooth), 1))
             {
     Plot0.Set(1);
     Plot1.Set(1);
             }
             // Condition set 2
             if (Plot0[0] >= 0 && Close[0] < EMA(50)[0]
                 && CrossBelow(MACD(fast, slow, smooth).Avg, MACD(fast, slow, smooth), 1))
             {
     Plot0.Set(-1);
     Plot1.Set(-1);
             }
             // Condition set 3
             if (Plot0[0] == 1 && Close[0] > EMA(50)[0]
                 && CrossBelow(MACD(fast, slow, smooth).Avg, MACD(fast, slow, smooth), 1))
             {
     Plot0.Set(0);
     Plot1.Set(2);
             }
             // Condition set 4
             if (Plot0[0] == -1 && Close[0] < EMA(50)[0]
                 && CrossAbove(MACD(fast, slow, smooth).Avg, MACD(fast, slow, smooth), 1))
             {
     Plot0.Set(0);
     Plot1.Set(-2);
             }
            // Use this method for calculating your indicator values. Assign a value to each
            // plot below by replacing 'Close[0]' with your own formula.
   }
   else
   {
    Plot0.Set(Plot0[1]);        
    Plot1.Set(Plot1[1]);   
   }
   Print(ToDay(Time[0]));Print(Plot0[0]);
        }
        #region Properties
 
  [Browsable(false)] // this line prevents the data series from being displayed in the indicator properties dialog, do not remove
        [XmlIgnore()]  // this line ensures that the indicator can be saved/recovered as part of a chart template, do not remove
        public DataSeries Plot0
        {
            get { 
    Update();
    return Plot0; }
        }
  [Browsable(false)] // this line prevents the data series from being displayed in the indicator properties dialog, do not remove
        [XmlIgnore()]  // this line ensures that the indicator can be saved/recovered as part of a chart template, do not remove
        public DataSeries Plot1
        {
            get {
    Update();
    return Plot1; }
        }
 
        [Description("Fast period for MACD")]
        [Category("Parameters")]
        public int Fast
        {
            get { return fast; }
            set { fast = Math.Max(1, value); }
        }
  [Description("Slow period for MACD")]
  [Category("Parameters")]
  public int Slow
  {
   get { return slow; }
   set { slow = Math.Max(1, value); }
  }
 
  [Description("Smoothing period for MACD")]
  [Category("Parameters")]
  public int Smooth
  {
   get { return smooth; }
   set { smooth = Math.Max(1, value); }
  }
        #endregion

What am I writing wrong?

[fx.practic]

1. Overlay = false;
2. replace everywhere "Plot0[0]" on Value[0], or on Values[0][0]
3. replace for each plot

        
public DataSeries Plot0
{
  get { 
          Update();
          return Plot0; 
          }
}

on

        
public DataSeries Plot0
{
  get { 
          Update();
          return Values[0]; 
        }
}

See in attach correct version, that works

And look on picture, how it works

[NinjaTrader_JoshP]

fx.practic,

You do not need to use Update() at all in these instances.

public DataSeries Plot0
{
       get { return Values[0]; }
}

[fx.practic]

Thank's Josh. Still don't know what Update() do - as well going to read manual

[NinjaTrader_JoshP]

Update() is for when you want to ensure another script referencing the first script will get most recent values. There may be special circumstances when you may not necessarily receive the most recent value when you start nesting a bunch of scripts. Use case for this is generally limited unless doing something fairly complex.

[takeo]

fx.practic and Josh, thanks for your kind advice