show continuously accumulating waveform chart

[abdel2]

I read around 1000 points per iteration that I would like to show on a waveform chart. If I just connect a numeric array to the Waveform Chart, it shows a smooth sin wave and it looks like it is just appending new data to the old one (kind of like a queue).

However, if I use a waveform, it overwrites the previous data with the new one. I want to see 2 seconds of data at any given time, so just showing 1000 points on a corner does not help.

I have tried appending to a waveform using shift register and it does show the result I want, but overtime the size of the waveform gets very large and it slows down the system. I could implement some size-checking and stuff, but is there

an easier way to make the waveform input behave a numeric array input?

I need to use waveforms because I want to stack multiple plots an it gives an "Out of memory" array if I use a 2D array.

[abdel2 · Accepted solution]

Got it working. Had to modify the timestamp in each iteration.

[sardarsree]

Hi,

I am vasu. I want to add cursors to wave chart. i can add cursors to wave graph. but i don't know how to add cursors to wave chart. plz send me that program to my mail(srinivas.perala@yahoo.com)

[Dennis_Knutson]

There is no way to add cursors to a chart. You will have to use a graph. If you need the ability to plot a point as it is acquired, you can use a shift register with a build array. Since this could lead to performance issues if the array grows with no bounds, you might want to incorporate a buffer like the chart does. There's an example called XY Chart that uses one.

p.s. NOT a good idea to post your email in a public forum. All you will get is spam. All questions are answered here and not by email.

Message Edited by Dennis Knutson on 02-24-2010 09:12 PM

[sardarsree]

Hi,

   Thank you. can you attach the program.

[Dennis_Knutson]

Why don't you go to LabVIEW, click on Help and then Find Examples?

[sardarsree]

No need to attach. I got the results. Thank you