Creating an indicator

[mrcartel]

Hello NT,

Could someone help me with creating an indicator? I am not that experienced and it seems a little confusing for me.

I am trying to create the following:

1. MovingAvg(High, 3) - (Avg True Range(3)*1)

2. MovingAvg (Low, 3) + (Avg True Range (3)*1)

[NinjaTrader_Matthew]

Hello,

Thank you for your post.

There are Moving Average and ATR methods you can easily reference in your code:

Moving Average - Simple (SMA)
Average True Range (ATR)

If you would like this plotted in the chart, you'd need to first set up the Plots in your Initialize() method. This method is called only once when adding your indicator to the chart.

    protected override void Initialize()
                {
                    Add(new Plot(Color.Green, "Upper"));
                    Add(new Plot(Color.Red,     "Lower"));
                    
                    Overlay = true;
                  }

We are also Initializing Overlay = true; to ensure these plots are drawn on the price panel.

Next, we can work in OnBarUpdate() which is called on each incoming tick and used to recalculate these values.

At this step, we will first need to store your calculations as a double value which can then be set in the plot. We are using the SMA() and ATR() methods as per your calculations requirements.

protected override void OnBarUpdate()
                {
                    
                    double ma1 = (SMA(High, 3)[0] - ATR(3)[0] * 1);
                    double ma2 = (SMA(Low, 3)[0] + ATR(3)[0] * 1);

Now that we have stored these calculations, we can set them in your plots:

Upper.Set(ma1);
Lower.Set(ma2);
}

Finally, we can setup the Plots as a public DataSeries that will allow you to change the properties of the plot from the UI

        #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 Upper
        {
            get { return Values[0]; }
        }

        [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 Lower
        {
            get { return Values[1]; }
        }

        #endregion

Hopefully this will help produce what you're looking for.

I would also like to add that the indicator you are creating is similar to our KeltnerChannel indicator. I'd suggest taking a look at the code in Tools--> Edit NinjaScript--> Indicator--> KeltnerChannel

I'm also providing some general educational material to help you get started with working with indicators.

You will find language references to all of the methods and functions you will be using. You will also see a tutorial section which will help you create your first indicator and get you started with some of these concepts.

A link to our Help Guide can be found below:
http://www.ninjatrader.com/support/helpGuides/nt7/index.html?distribution.htm

I am also linking you to the Educational Resources section of the Help Guide to help you get started with NinjaScript:
http://www.ninjatrader.com/support/helpGuides/nt7/index.html?educational_resources.htm

We also have some Reference Samples online as well as some Tips and Tricks for both indicators and strategies:

• Click here to see our NinjaScript Reference Samples
• Click here to see our NinjaScript Tips

These samples can be downloaded, installed and modified from NinjaTrader.

Please let me know if there is anything else I can do for you.

[mrcartel]

I did the 1st two steps and saved. Everything is fine thus far.

1. Where do input step 3 below? Do I add that where the color of the plots in step 1 that you told me?

2. The 4th step does that goes in the area of line 48 thru 63 (Properties).

3. Are there any videos to watch for future purposes?

[NinjaTrader_Matthew]

Hello,

Step 3 would go directly under step 2. All of this information is put in OnBarUpdate() between the opening ({) and closing braces (})

protected override void OnBarUpdate()                 
{                                          

    double ma1 = (SMA(High, 3)[0] - ATR(3)[0] * 1);                    
    double ma2 = (SMA(Low, 3)[0] + ATR(3)[0] * 1);

     Ma1.Set(ma1); 
     Ma2.Set(ma2); 
}

The color for the Plots go above OnBarUpdate() in the Initialize() method


Yes, the last step goes into in the Properties region.

We have a few videos for you to watch

Learning NinjaScript:

http://www.youtube.com/watch?v=JZpo01eSO9c&list=PL82A14C398CA140D7&index=14&feature=plpp_video

Automated Strategy Development Webinar:

http://www.youtube.com/watch?v=fVFqw5W8uGI&list=PL4D56536A44DD7105&index=10&feature=plpp_video

[mrcartel]

Mr. Matthew,

I did everything you told me to do and saved it. I am getting an error message (Error on generating Indicator). Below that it has the following

CS0201 line 45, col 13
CS1061 line 45, col 19
CS0103 line 45, col 38
CS0103 line 48, col 6
CS0103 line 49, col 6

[NinjaTrader_Matthew]

Can you copy and paste the entire code you tried using?

[mrcartel]

protectedoverridevoid Initialize()
{
Add(new Plot(Color.Green, "Upper"));
Add(new Plot(Color.Red, "Lower"));

Overlay = true;
}
///<summary>
/// Called on each bar update event (incoming tick)
///</summary>
protectedoverridevoid OnBarUpdate()
{
double ma1 = (SMA(High, 3)[0] - ATR(3)[0] * 1);
double ma2 = (SMA(Low, 3)[0] + ATR(3)[0] * 1);
Ma1.Set(ma1);
Ma2.Set(ma2);
}

[NinjaTrader_Matthew]

Sorry, there was a typo in the code I typed before. Rather than using Ma1.Set(ma1), please use Upper.Set(ma1);

    protected override void Initialize()
            {
            Add(new Plot(Color.Green, "Upper"));
            Add(new Plot(Color.Red, "Lower"));

            Overlay = true;
            }
            ///<summary>
            /// Called on each bar update event (incoming tick)
            ///</summary>
            protected override void OnBarUpdate()
            {
            double ma1 = (SMA(High, 3)[0] - ATR(3)[0] * 1);
            double ma2 = (SMA(Low, 3)[0] + ATR(3)[0] * 1);
            Upper.Set(ma1);
            Lower.Set(ma2);
            }

        #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 Upper
        {
            get { return Values[0]; }
        }

        [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 Lower
        {
            get { return Values[1]; }
        }

        #endregion

[mrcartel]

Hey Matt,

I did exactly what you told me and I have an error message for line 45, col 13,19, & 38.

The codes are cs0201, cs1061, & cs0103

Sorry I am not good at this but I do appreciate your help.

[mrcartel]

Matt,

Line 45 would be double ma1 = (SMA(High, 3) [0] - ATR (3) [0] * 1):

Should there be any spacing? however, there is spacing the 2nd formula and no error messages came up

[NinjaTrader_Matthew]

The spacing should not matter.

From your code do you have a colon or semicolon? It should end with a semicolon.

I've attached a .zip file which contains a version of this indicator which should compile, and should also result in the image attached when applied to a chart.