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Build waveform from discrete points

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Hello all

 

I am trying to make a custom signal generator with the possibility of an arbitrary waveform. 

I have a graph with some cursors on it you can move around as you like (only in the Y direction, not the X) From these points I would like

to create a "soft" waveform, that is a waveform with lets say 500 points so the edges isn't so rough. I have attached some pictures showing what I

have and what I would like 🐵 (I have the discrete and I would like a waveform smoothness like the output)..

I tried to mess around with FIR filter, interpolation, spline functions but I don't think it is the way to go because of the low amount of datapoints I have to start

with, but maybe these functions could be a step two in the process?!

This curve is something the user is going to draw each time he starts the program, that's why I am kind of limited to around 10-20 points max to create a waveform

like the one in the picture.

 

Hope you understand my problem and are able to help. 🙂

 

Thanks

 

Regards

Tommy

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Running LabVIEW 2009 32bit SP1 on Windows 7 64Bit
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I saw the effects of the Cubic Hermite Spline Fit durring a demo and told myself "I should rember that one" for those cases where other fits give weird ringing type effects nears steps. So I never got around to using it but at least I rembered it.

 

I hope that helps you,

 

Ben

Retired Senior Automation Systems Architect with Data Science Automation LabVIEW Champion Knight of NI and Prepper LinkedIn Profile YouTube Channel
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Hello Ben

 

Thanks for your input, I'll give it a try.

 

Have a nice day

 

Regards

Tommy

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Accepted by topic author tombech

here is my try... My quick input was an array of slider 😉

 

 If you run it in a loop the operator get's a direct feedback.

Why you don't like  splines? 

 

Sidenote: If you choose  coerce for interpolation, you have a Pisa like impression 🙂

 

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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Hello

 

Thanks to both for good answers!!

 

Henrik: I don't mind spline functions, I just though it would require more points then what I had, but I see it works great.

Nice little example you made there, thanks a lot it works great!!!!

 

Have a nice weekend, I know I will now 🙂

 

Regards

-Tommy

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