Can XY Graph add a single point to a plot without redrawing previous points?

[altenbach]

What's the point of the FOR loop on the right and the outer case structure in it?

What's the point of the sequence structure?

You did not include the subVI. Can you attach it too?

When things slow down, adding a delay seems counterintuitive. 😄

You have more rows than graphs, how do you expect to display each row on a separate graph? Pleade describe in more details what you actually want...

[developer001]

sorry there were a few extra things in there for testing purposes, so I took them out!

Actually my input array would ideally be 128x40, and i did not want to have to go through and create 128 cases for the graphs. so i just created 3 for now.

I kind of just added the delay based on my understanding from the previous replies...not sure though!

anyways ive attached all the vis here.

Oh and I want to generate the random data at 20 Hz(this is the freq I will be reading in actual values later on).

Why does the random array get slower and slower?

Thanks!

[johnsold]

Please attach the XY_Chart-display.vi.  Good chance the problem is in there.

Lynn

[developer001]

Its actually in the Untitled 4(SubVI) part.

[johnsold]

It is a subIV to Untitled 4.  As such it is a separate file just as Untitled 4 is a subVI to generateRandArray2.vi.

Lynn

[developer001]

Sorry

For some reason I cannot save these vis, I cant make any changes to them either.

I attached a screen shot of their block diagrams instead.

[developer001]

Never mind I found it!

[altenbach]

OK, you basically mutilated the stock "built xy graph" express VI. Why did you not keep the stock version?

Your internal data structures grow forever, constantly needing to allocate new data of increasing size. That's why things slow down. At one point, you'll run out of memory.

Your inner case 0 is also default, so it will get 126x more data than the other graphs. Is this really what you want?

Case 1 gets row 1, case 2 gets row 2, and case 0 gets row 0 as well as 3..127.

[developer001]

not really sure how I did it!

Ok so I just added the real build xy graph express vi, and it seems ok.

But do you mean my change caused the internal data structure to grow forever?

and yes for now it is ok that case 0 is default, it will be solved when i added a separate graph for each case.

[altenbach]

I would make an empty "-1" case and make it the default. No need to do all that extra work.

Is the built xy graph express VI set to retain data between calls?

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@developer001 wrote:

not really sure how I did it!

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You right-clicked the express VI and selected "open front panel". This converts it to a plain VI that you can customize if you want. Not needed here.