How do i create arrays more efficiently

how do i create arrays more efficiently?... need to insert data into an array every loop iteration. I am using the insert into array function and shift registers. I have been told this is inefficient... and they are right because I can make the program stop and it gives me the error that labview does not have enough memory. A coworker said to avoid shift registers and investigate property nodes... i am new at this and don't know what this is exactly.. is there a tutorial on efficent data handling.. or examples that would be usefull?

tbob wrote:
Mark is absolutely correct. Indexing will take a lot of memory and a lot of time when the array gets large. Indexing is great for small arrays though. With indexing, the first loop iteration will create an array of size 1. On the next loop, the array has to be copied, re-dimensionedcto size 2, old data copied to new array, and new data inserted at end. You can see how this will become a monster with an array size of 10,000. With pre-allocation, there is no re-dimensioning and no copying. Array elements are simple replaced. And yes you do have to know the upper limit to use pre-allocation. Kudos to Mark for pointing out the facts.
A bit of a clarification is needed. Folks from NI told me that LabVIEW tries to be smart when autoindexing. When they allocate the memory the initial chunk of memory it is larger than a single element. So you don't necessarily get a copy and allocation every iteration. They may have improved the optimization to preallocate the complete array if the size is already known (a constant wired to the loop count). However, they would have no way of doing this if the number of iterations is not known ahead of time.
Mark Yedinak
"Does anyone know where the love of God goes when the waves turn the minutes to hours?"
Wreck of the Edmund Fitzgerald - Gordon Lightfoot

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Solved!
Go to Solution.
Attachments:
next state.jpg ‏75 KB

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Attachments:
forum nov 12 red green blue.vi ‏7 KB
forum nov 12 red green blue.ctl ‏5 KB

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I want to create some arrays with names like array1,
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Attachments:
regulation_tester_7_loops.vi ‏244 KB

I didn't really have time to dig in and understand your program in depth,
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"nelsons" wrote in message
news:[email protected]...
> how do I create a 1d array that takes a single calculation and insert
> the result into the first row and then the next calculation the next
> time the loop passes that point and puts the results in thsecond row
> and so on until the loop is exited.
>
> The attached file is work inprogress, with some dummy data sp that I
> can test it out without having to connect to equipment.
> The second tab is the one that I am having the problem with. the
> output array from the replace element appears to be starting at the
> index position of 1 rather than 0 but that is ok it is still show that
> the new data is placed in incrementing element locations. However the
> main array that I am trying to build that is suppose to take each new
> calculation and place it in the next index(row) does not appear to be
> working or at least I am not getting any indication on the inidcator.
>
> Basically what I am attempting to do is is gather some pulses from
> adevice for a minute, place the results for a calculation, so that it
> displays then do the same again the next minute, but put these result
> in the next row and so on until the specifiied time has expired and
> the loop exits. I need to have all results displayed and keep building
> the array(display until, the end of the test)Eventually I will have to
> include a min max section that displays the min and max values
> calculated, but that should be easy with the min max function.Actually
> I thought this should have been easy but, I gues I can not see the
> forest through the trees. Can any one help to slear this up for me.

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Solved!
Go to Solution.
Attachments:
forum dec 12_2012 build 2d array.vi ‏13 KB

dav2010 wrote:
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Attachments:
Initialize_Settings.vi ‏55 KB
Save_Settings.vi ‏52 KB

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