Using Structs with Indicator within Strategy

[r2kTrader]

Hi all,

I am trying to implement the following from within the variables section and it is throwing an error.

private double[] test = SMA(fast)[0];
private double testCurrentBar = test[1];

Then in my code I want to do something like:

if (testCurrentBar > 0)

---Note---
I am not really interested in SMA, rather any indicator and getting the value of the indicator for the current bar, last bar, bars back, etc.

I'm just tired and it's not clicking, if anyone could lend a hand it would be appreciated.

[NinjaTrader_Josh]

r2kTrader,

I really don't understand what you are trying to do. If you want the SMA's value of the current bar just go SMA(Fast)[0]. If you want the previous bar just go SMA(Fast)[1]. Not following your reason for needing double[].

[r2kTrader]

Originally Posted by NinjaTrader_Josh

r2kTrader,

I really don't understand what you are trying to do. If you want the SMA's value of the current bar just go SMA(Fast)[0]. If you want the previous bar just go SMA(Fast)[1]. Not following your reason for needing double[].

I'm trying to setup a Array that can hold the values so I can then just access the variable. I don't want to have to type in SMA(Fast)[0] for every instance I compare, rather I just want to say currentBar or whatever.

Would I need a DataSeries for this?

Easier to do

if(testCurrentBar - testLastBar > 0)

{
//do something
}

Than

if(SMA(Fast)[0] - SMA(Fast)[1] > 0)

so this is what I am trying to do. I want my code cleaner and more readable.

Thanks

[NinjaTrader_Josh]

Doing such an operation will be inefficient for the code. If you only want to compare current and last just create two double variables to store those values. Otherwise you would need to make a whole DataSeries which is essentially doubling the resources of just calling SMA directly.

[r2kTrader]

Josh,

That is what I am asking how to do

Can you spit me a snippet?

[junkone]

i think what Josh is suggesting is
currentVal=SMA(Fast)[0];
prevValue=SMA(Fast)[1];

bool result =currentVal>prevValue?true:false;

.
not wanting to hijack this thread but to extend it.
would calling the dataseries everytime make it recalculate the data
for eg, SMA(Fast)[0] calculate the values for alteast <fast> periods and get the current value

SMA(Fast)[1] calculate the values for alteast <fast> periods and get the prev value

[r2kTrader]

Junkone,

Thanks for jumping in.

This is what I did:
double poCurrentBar = Oscillator(PoFast, PoSlow, PoSmooth)[1]; //not zero because we calc on bar close for this osc - FirstTickOfBar
double poOneBarsAgo = Oscillator(PoFast, PoSlow, PoSmooth)[2];
double poTwoBarsAgo= Oscillator(PoFast, PoSlow, PoSmooth)[3];
double poThreeBarsAgo= Oscillator(PoFast, PoSlow, PoSmooth)[4];

But is this efficient? Wouldn't it be better to call it once than 4 times?

How come it won't accept

double[] poCurrentBar = Oscillator(PoFast, PoSlow, PoSmooth)[1];

It says can't convert type double to type double[]

I'm a student of C#, so any help would be appreciated.

PS,

I like the idea of the bool, would be more efficient.

[r2kTrader]

Josh,

Could you look at my code and let me know if I am calling the Oscillator more than is necessary? I wanted to call it once per bar update and then just load the array and reference the array, but it won't let me do a double[] from a double.

[NinjaTrader_Josh]

junkone,

When called from within the same script there already is an instance of the indicator in memory so it doesn't recalculate twice.


r2kTrader,
double[] is an array while Oscillator(...)[1] is a double. That is why you get the cannot convert message.

Try this untested code. Unfortunately I cannot provide more assistance than this. You can try searching google for examples.
double[] someVar = new double[4];
someVar[1] = Oscillator(..)[1];

Calling Oscillator() four times in your code is no more or less efficient than calling it once since it is already in memory.

[r2kTrader]

Originally Posted by NinjaTrader_Josh

junkone,

When called from within the same script there already is an instance of the indicator in memory so it doesn't recalculate twice.


r2kTrader,
double[] is an array while Oscillator(...)[1] is a double. That is why you get the cannot convert message.

Try this untested code. Unfortunately I cannot provide more assistance than this. You can try searching google for examples.
double[] someVar = new double[4];
someVar[1] = Oscillator(..)[1];

Calling Oscillator() four times in your code is no more or less efficient than calling it once since it is already in memory.

Then an array would just be redundant. Thank you for this update, very helpful.