Code problems

[Burga1]

Greetings,

I'm new to NinjaTrader. I'm trying to code my first indicator. Can somebody please point out what the errors are with the following code I wrote, it appears I have a problem with definitions:

double StK = 0; double Pr = 0;
MAX Diff1 = MAX(StK,Pr); MIN Diff2 = MIN(StK,Pr);

The error codes given after the compile:

"The best overloaded method match for Ninjatrader.Indicator.Indicator.MAX(NinjaTrader,Da ta,IDataSeries,int) has some valid arguements"
"Cannot convert from double to Ninjatrader.Data.IDataSeries"
"Cannot convert from double to int"

[NinjaTrader_JoshP]

Hi Burga1,

MAX and MIN are methods not object types. They are used for determining max and mins on DataSeries objects though instead of just comparing two doubles. Instead you want to use Math.Max and Math.Min for what you are trying to do.

http://www.ninjatrader-support.com/HelpGuideV6/MaximumMAX.html

http://www.ninjatrader-support.com/HelpGuideV6/MinimumMIN.html

[FONT=Courier New][SIZE=2][FONT=Verdana]double StK = 0;
double Pr = 0; 
double Diff1 = Math.Max(StK, Pr);
double Diff2 = Math.Min(StK, Pr);[/FONT][/SIZE][/FONT]

[Burga1]

Hi,

Thanks for the response, that seems to take OK so what is the following with the following, it is also a min/max definition...


double MIN1 = Math.Min(Low,K); double MAX1 = Math.Max(High,K);

On a related note, is the following code acceptable?

StK = ((Close - MIN(Low,K)) / (MAX(High,K) - MIN(Low,K))) * 100;

Thanks in advance.

[NinjaTrader_JoshP]

Low and High are series objects. You will need to tell it exactly which Low and which High you want to compare. For example, if you want the current bar's Low you would do Low[0]. The previous bar's low can be referenced by Low[1].

[FONT=Courier New][SIZE=2][COLOR=#0000ff]double[/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2] MIN1 = Math.Min(Low,K); [/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff]double[/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2] MAX1 = Math.Max(High,K);[/SIZE][/FONT]

should probably be

[FONT=Courier New][SIZE=2][COLOR=#0000ff]double[/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2] MIN1 = Math.Min(Low[0], K); [/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff]double[/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2] MAX1 = Math.Max(High[0], K);[/SIZE][/FONT]

and

StK = ((Close - MIN(Low,K)) / (MAX(High,K) - MIN(Low,K))) * 100

should be something like

[FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]StK = ((Close[0] - MIN(Low, K)[0]) / (MAX(High, K)[0] - MIN(Low,K)[0])) * [/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080]100[/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2];[/SIZE][/FONT][/SIZE][/FONT]

Also make sure K is an integer.

[KBJ]

It looks like you're trying to code something to do with a Stochastics indicator.

If so, you might want to have a look at the source code for the Stochastics indicator that is stardardly supplied with NinjaTrader. Click on Tools/EditNinjaScript/Indicator and select Stochastics.

If you do this, you will notice code that looks very similar to what Josh just posted for you.

[Burga1]

Thanks again for the help. Where are my variable definitions supposed to be? Should they be listed in the "protectedoverridevoid Initialize()" function?

thanks again.

[KBJ]

The variable definitions would either be defined just before the "protected override void initialize()" method or just before they're used in OnBarUpdate() if it's a temporary variable (i.e., not used outside OnBarUpdate.)

[Burga1]

Thanks again. The definitions are not what I'm used to, a bit more confusing...

I'm trying to convert this line into something recognized by Ninja:


StVarK = SMA((((VarSto - MIN(VarSto, K)) / (MAX(VarSto, K) - MIN(VarSto, K))) * 100), Sl);

I've tried:

double VarSto1 = Math.Min(VarSto, K); double VarSto2 = Math.Max(VarSto, K);
SMA StVarK = new SMA((((VarSto - VarSto1) / (VarSto2 - VarSto1)) * 100), Sl);

I seem to get an error on the definition--however I took it straight from the online Help...

Thanks KBJ I'll take a look...

Regards

[NinjaTrader_JoshP]

SMA isn't an object type. What you want to try and do is create a DataSeries object that contains your mathematics. Then you want to run the SMA on that DataSeries.

http://www.ninjatrader-support.com/HelpGuideV6/DataSeriesObject.html

#region Variables
    private double VarSto = 0;
    private double VarSto1 = 0;
    private double VarSto2 = 0;
    private double StVarK = 0;
    private int S1 = 20; // Period variable for the SMA
    private DataSeries myDataSeries;
#endregion
 
protected override void Initialize() 
{ 
    myDataSeries = new DataSeries(this);
}

protected override void OnBarUpdate()
{
    VarSto1 = Math.Min(VarSto, K);
    VarSto2 = Math.Max(VarSto, K);
    myDataSeries.Set(((VarSto - VarSto1) / (VarSto2 - VarSto1)) * 100);
    StVarK = SMA(myDataSeries, S1)[0];
}

[Burga1]

Thanks, is this the correct approach to code every SMA or EMA whenever they are needed?

Regards

[NinjaTrader_JoshP]

This approach can be used to get the SMA, EMA, etc. values of whatever calculation you are doing. I'm sure there are other acceptable ways to do it, but this is the way I most commonly employ.

[Burga1]

Greetings,

Why does the compiler give me errors with this code?

#region Variables
private DataSeries myDataSeries2;
#endregion

protectedoverridevoid Initialize()
{
...
myDataSeries2 = new DataSeries(this);
...
}

protectedoverridevoid OnBarUpdate()
{
...
myDataSeries2.Set(((1 - MyConst) * (VarSto[1])) + (MyConst * Close)); //ERROR ON THIS LINE...
if(CurrentBar < (Pr + (Pr * 1.5))){VarSto = StK;}
else{VarSto = SMA(myDataSeries2, 2)[0];}
...
}

[KBJ]

It's hard to tell with just part of the code and variable definitions.

But, assuming that this is part of the code from Josh's post (#9, below), then the problem is that VarSto is a scalar double, but you're referencing it as an array element or a dataseries element.

So, change the "VarSto[1]" to just "VarSto" and the compile error will go away.

I don't know if the code will work, but this particular error will be gone.

[Burga1]

Thanks. Here's the code I'd like to convert (from another app.):

VarSto:= If(Barnum<Pr+(Pr*1.5),StK,MOV((((1-MyConst)*Ref(VarSto,-1))+(MyConst*Close)),2,s));

NOTE: Read as "IF(statement, then do this, else do this);"...

The problem seems to be with the way NT requires moving averages to be coded, I'm not sure how to perform the "else" part of the previous statement correctly...

if(CurrentBar < (Pr + (Pr * 1.5))){VarSto = StK;} //this is OK

For the "else" statement, I need to define the "myDataSeries2.set" BEFORE I assign the VarSto variable a value...but if the "else" statement is called the VarSto has no value...I think that's the problem???

else
{
myDataSeries2.Set(((1 - MyConst) * (VarSto[1])) + (MyConst * Close)); //Error on this line, because VarSto has no value??
VarSto = SMA(myDataSeries2, 2)[0];
}

[NinjaTrader_Ray]

"Close" is not correct, likely you want Close[0].