Curvefitting after FRF function

[Tim R]

Hi

when I open my saved measurement data I can display the Frequency response with FRF function. When running the VI I can display the FRF with an average number. This is real time. So the measurement is averaging each iteration.
When I save this data, only one single sample will be saved. So averaging will be useless when I open the measurement. I would like to see the same FRF graph when I open the measurement as when I do a measurement real time.

[altenbach]

Your question is a bit confusing.

• If you want the averaged data later, why don't you save the averaged data instead of a single sample? 😉
• If you want to average the stored data later, you must save all samples.

Maybe you can attach a small example program to illustrate what you want?

[Tim R]

Thanks for your reply.

What I am saving is a sample of the incoming signals. Therefor I use the labview save and read measurement file. So in this case I can manipulate my saved signals in another VI.
A solution is to save multiple signals, only I don't know how to do this. Saving the averaged data is not possible because I have to save the incoming signals.

[Tim R]

Sorry, didn't mean: save multiple signals, but multiple samples...

[RikPrins]

Hello,

It is not quite clear to me what you are doing. How are you measuring the data? In what format is it displayed? Do you meaure one sample per itteration, or multiple samples?

As mentioned in the post of mister Altenbach, an example on how you set it up right now would help greatly.

Regards,

RikP

Application Engineering NI

[Tim R]

So, I ve attached my VI's I use to write and read data. Also I attached a frequency response measurement done with an analyzer. And a pretty similar measurement done with labview.
You can see the difference in noise ratio. So what I would like to see is the same graph in labview as with the analyzer.

[Tim R]

Here is another measurement done with labview. This is a real-time measurement.  This is  what I would like to see in the saved measurementfile.