Unable to update an array element?

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I am trying to convert an indicator to an EA...all works well with one frustrating exception.


One section of the routine sets an array element equal to a variable...eg: "myArray[myElement] = myVariable". myArray and myVariable are both defined as "double". This works perfectly fine in the indicator, but in the EA, after the statement is executed, myArray[myElement] is equal to zero...even though myVariable contains a value. I have put "Print" statements before and after to verify that myVariable contains a value...but myArray[Element] contains a value of zero before and after the statement gets executed.


It's probably something obvious, but I'd appreciate some direction...TIA.

 
ChuckM:

[...] It's probably something obvious [...]

Are you sure the array is large enough? For example...


double MyArray[2]; MyArray[2] = 999; // Slot 2 doesn't exist; array has bounds 0 to 1 MessageBox("Value is not 999: " + MyArray[2]);


 
jjc:

Are you sure the array is large enough? For example...


double MyArray[2];
MyArray[2] = 999; // Slot 2 doesn't exist; array has bounds 0 to 1
MessageBox("Value is not 999: " + MyArray[2]);



It is defined in the EA the same way it is defined in the indicator...

double myArray1[];

Do indicators and EAs treat arrays differently?

 

Well...I just answered my own question...it turns out that they do treat arrays differently. When I was testing, I looked in the journals and never saw an indication of an error.


After I made the previous post, it occurred to me that although I used the "Print" function, I never used GetLastError() to see if the statement generated an error. Sure enough...I got an array index error.


Now that I know what the problem is, I can correct it...sure wish I knew where this is documented. Thanks, jjc.

  
ArrayResize()
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