Hi guys, I had a block of code that I’ve used in many strategies. I created a user defined function today so that I can just call it in my strategies. This way, anytime I need to make changes to the function.. I can amend the function and it changes it in all my strategies. One of those functions is simple... calculating position size

 

Code

// public static void AccountCalcualtion(SystemPerformance systemperformance, double AccountSize, double RiskPercent, double Leverage, double fxToBuy1, double total_fundUSD) // { // double CumProfits= (systemperformance.AllTrades.TradesPerformance.Currency.CumProfit); // total_fundUSD= (AccountSize+CumProfits); // double dummyQ = (((int)Math.Floor((total_fundUSD*RiskPercent))) * Leverage); // fxToBuy1 = ((int)(dummyQ/1000))*1000; // NinjaTrader.Code.Output.ProcessfxToBuy1), PrintTo.OutputTab1);

Then I am calling this function in my strategy as

AccountCalculation();

It works, it prints out the correct position size that my strategy would had calculated.

Problem: I can’t seem to assign the values from this function to a variable within my strategy so that I can use it.

I keep getting an error “can’t convert void to double”

I just want to take the value that this function is calculating and then assign it to a variable for the position to purchase.... any help would be appreciate

Hi calhawk01,

using void as the return type for a method specifies that the method doesn't return a value. You could change it to double and have the method return a double value (via the return keyword) when called.
You can find more information here: https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/methods

Regards,

ABCTG

@calhawk01

Use return parameter as @ABCTG described above, or prefix your fxToBuy1 parameter with the 'out' keyword, see following for info:

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/out-parameter-modifier


[Note that when using public static for shared functions it is best to use a naming prefix to avoid namespace clashes, and also that compiling will cause links to be broken until all charts/strats are F5'd or reopened. (I do use this mechanism a lot and would like to find a good solution to that problem.)]

Another alternative is to use the 'partial class' mechanism for instanced funtions.

ABCTG 

Hi calhawk01, using void as the return type for a method specifies that the method doesn't return a value. You could change it to double and have the method return a double value (via the return keyword) when called. You can find more information here: https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/methods Regards, ABCTG

Thank you.

 

Code

namespace NinjaTrader.NinjaScript.Strategies { public partial class Strategy { public static double AccountCalcualtion(SystemPerformance systemperformance, double AccountSize, double RiskPercent, double Leverage, double fxToBuy1, double total_fundUSD) { double CumProfits= (systemperformance.AllTrades.TradesPerformance.Currency.CumProfit); total_fundUSD= (AccountSize+CumProfits); double dummyQ = (((int)Math.Floor((total_fundUSD*RiskPercent))) * Leverage); fxToBuy1 = ((int)(dummyQ/1000))*1000; // NinjaTrader.Code.Output.ProcessfxToBuy1), PrintTo.OutputTab1); } } }

I had tried using double. However, NT won't compile with a double.

the error:

 

Code

NinjaScript File Error Code Line Column StrategyFunctions.cs 'NinjaTrader.NinjaScript.Strategies.Strategy.AccountCalcualtion(NinjaTrader.Cbi.SystemPerformance, double, double, double, double, double)': not all code paths return a value CS0161 46 25

Still trying to get this to work :/

I'm not a programmer so i think the problem is pretty basic but b/c i don't have the background i'm stuck. i've been working with ninjascript for about 4 years and am well verse in creating strategies... just never done anything like this. would appreciate if someone can help! i think once i get this to work i should be good to go with various other functions that i need to create..

The error is due to you declaring return of type double but not returning any double value from your function so you need eg:

return fxToBuy1;


Just put a return and then whatever variable value you need to pass back in your function.


Sent from my iPhone using NexusFi

iq200 

The error is due to you declaring return of type double but not returning any double value from your function so you need eg: return fxToBuy1; Just put a return and then whatever variable value you need to pass back in your function. Sent from my iPhone using NexusFi

Thank you, iq200.

I finally had the chance to try your suggestion. I'm good to go!

Working code:

 

Code

namespace NinjaTrader.NinjaScript.Strategies { public partial class Strategy { public static double fx_Position_Size(SystemPerformance systemperformance, double AccountSize, double RiskPercent, double Leverage) { double Total_Profit = systemperformance.AllTrades.TradesPerformance.Currency.CumProfit; double total_fundUSD= AccountSize+Total_Profit; double dummyQ = (((int)Math.Floor((total_fundUSD*RiskPercent))) * Leverage); double fxToBuy = ((int)(dummyQ/1000))*1000; return fxToBuy; } } }