Drawing dots based on a condition

[rdhtci]

I am new to coding in NinjaTrader. I am trying to draw a dot beneath bars based on a condition being true. I found the topic partially covered in an older thread at this link:

http://ninjatrader.com/support/forum/showthread.php?t=65414

From that thread, I gather that I should use DrawDot rather than Plot when the dots are not to be drawn on every bar.

I have this working for a condition based on the current bar, but it fails when I try to make the condition refer to previous bars.

So, using this condition, I can get the dots to display correctly.

if (Close[0] < Open[0])

But, if I try to refer to previous bars, like this:

if (Close[0] < Open[1])

-- the code does not work. So, I assume it is the condition itself which I am getting wrong.

Can anybody explain why this change would stop the code working, and how I would correctly refer to previous bars?

Any help appreciated.

Here's the rest of the code.

protected override void OnBarUpdate()
    {

        {   

            //if (Close[0] < Open[0]) 
            if (Close[1] > Open[1])
            //if(Close[1] < Close[0] && Close[1] < Close[2])

                { 
                    myBarCloses=1;
                } else {
                    myBarCloses=0;
                }

                if (myBarCloses==1) 
                {
                    DrawDot(CurrentBar.ToString() +"BarCloseDot",true, 0, Low[0]*0.997, Color.Magenta);
                }

        }      

    }

[sledge]

Can anybody explain why this change would stop the code working, and how I would correctly refer to previous bars?

If you look in the log tab you should see an error message I believe.
Open an output window and you will definitely see the error (where I always look).

This link should explain and solve your problems:

http://ninjatrader.com/support/forum/showthread.php?t=3170

[rdhtci]

Thanks very much for the assistance, I have it working with the suggestions in the link you provided.

Interested in your other suggestions too. I can't find anything relevant in the log tab, and I see nothing at all in the output widow, I would be interested to know how I actually get a visible output.

[sledge]

Interested in your other suggestions too. I can't find anything relevant in the log tab, and I see nothing at all in the output widow, I would be interested to know how I actually get a visible output.

The output window should be open when the error happens:

It would say something like this:

"5/3/2016 11:22:54 AM Strategy Error on calling 'OnBarUpdate' method for strategy 'a1xWnew/271b9005ace94801b857c51c1ba907d5': You are accessing an index with a value that is invalid since its out of range. I.E. accessing a series [barsAgo] with a value of 5 when there are only 4 bars on the chart."

You can simply call "Print" command to print to the output window.

Print ( "Close[0]=" + Close[0] );

[rdhtci]

Thanks again. Much appreciated.