Hello community,

I request support for the following problems:

1. I want to use a counter in a method. This does not yet work thread safe.
Sample 1a would be encapsulated but does not return a correct value.
Sample 1b works, but is not thread-safe (==> Sample2)

2. How can I use predecessor values in a method?
Sample 3 shows that no previous value is determined with this procedure.
Analog Sample 1b I can initialize the series outside the method; this solution is also not thread safe.

I gave the examples because I want to simplify my request.

I make 5 calculations with different values, but they always have the same conditions.
This requires a TickCounter and a previous value.

That's why I want to do the calculations in a method, using thread-safe variables.
My programming example shows that reusing a variable does not work if it is initialized outside the method.
I would have to use 5 variables or series for my 5 calculations, so that the method actually makes no sense.
Finally, methods should simplify the code and "save" variables.

There are suggestions on how I can solve the problem?

Thank you!
Best
user10



PS: Are there any examples of function programming in the forum; I did not find any.

 

Code

namespace NinjaTrader.NinjaScript.Strategies {     public class TestFunktionen : Strategy     {         private SMA SMA1;         private int barCounter;         private int barCounterFuncIn;         private int barCounterFuncIn1;         private int barCounterFuncIn2;                  private int funktionsValue;         private int funktionsValue1;         private int funktionsValue2;                  protected override void OnStateChange()         {             #region notrelevant                          if (State == State.SetDefaults)             {                 Calculate    = Calculate.OnEachTick;             }             else if (State == State.Configure)             {                 AddDataSeries(Data.BarsPeriodType.Minute, 1);             }             else if (State == State.DataLoaded)             {                             }             #endregion         }         protected override void OnBarUpdate()         {             // OnBarUpdate             barCounter++;                          // Funktionen             funktionsValue = barCounterF();             funktionsValue1 = barCounterThread();             funktionsValue2 = barCounterPrevious();                          Print (Time[0]                  + "  barCounterF   " + funktionsValue              + "  barCounterThread   " + funktionsValue1              + "  barCounterPrevious   " + funktionsValue2                 + "  barCounter   " + barCounter);         }             public int barCounterF()                    // Sample 1             { //                int counter = 0;                // Sample a     //                return counter;                // returns 1                                  barCounterFuncIn++;            // Sample b                 return barCounterFuncIn;        // not thread-safe             }                  public int barCounterThread()                // Sample 2             {                 barCounterFuncIn +=2;                 return barCounterFuncIn;           // not thread-safe             }                          public int barCounterPrevious()        // Sample 3             {                 Series <int> barCounterSeries = new Series<int> (this);                 barCounterFuncIn2++;                 barCounterSeries[0] = barCounterFuncIn2;                  //                return barCounterFuncIn2;        // correct                 return barCounterSeries[0];        // correct //                return barCounterSeries[1];        // ==> 0 ==> no previous Value             }

It’s simple to make a part of your code single threaded.

Add a class member first:

private static object lockObject = new object();


And then in your code where you want to make single threaded do this:

lock(lockObject)
{
// do your work here - threadsafe
}

If you only want to make an increment safe you do not need the above. You can do it in a simple command like this

return Interlocked.Increment(ref COUNTER);

Hello LukePoga,

Thanks for the hint.
In the meantime, I've learned that threadsafe is probably the wrong name.

I calculate values in periods whose beginning and end are indefinite. At the end of the period I would like to do another calculation;
because the condition is wrong at this time, I need to access the predecessor value.
In real-time operation, this condition is true for one bar, but the condition should only be true for a tick to execute the calculation once.
These 5 calculations are performed with different values and periods and all five should access one method.

I understand that I can initialize variables and series outside the method.
Then both the counter and the return of the previous value will work.

In my example barCounterF () and barCounterThread () I increase the same variable barCounterFuncIn once by 1 and once by 2 and return it.
Although I assign a different variable (functionValue1 and functionValue2) to the respective return value, the methods influence each other.

If I change the barCounterThread () method to another variable e.g. assigning barCounterFuncIn1, both methods provide the correct result.

I added the code for verification.

If I want to simplify my code, this must not happen. It also makes no sense to use exactly the variables and series that I would have to use without any method.

Where is my mistake?

Best
user10