Sampling sine wave and saving the samples in an array.

helo..
I am new to Labview and i need some help regarding sampling the sine wave.
I have generated the sinewave in labview and now i want to sample it.(do i need an ADC for sampling?) and the samples should be saved in an array.
I dont know how to do this.
Please tell me how to do this or post some related examples..
Thanks in advance

All of the functions that generate a sine wave in software do save all of the samples in an array. You just need to know how to get them. Since you did not mention the function you used to create the sine wave, lets assume it's the Express VI Simulate Signal. On the signal output, wire a Convert From Dynamic Data type function and select the default 1d Array of Scalars. Right click on the output of this and select Create Indicator. You now have the array. If you are using Sine Waveform which outputs a waveform data type, just wire up a Get Waveform Components function and select the item 'Y'.
For learning the basics, please see the free tutorials
Message Edited by Dennis Knutson on 10-28-2008 08:23 PM
Attachments:
Get Y Array.PNG ‏4 KB

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bhardoo wrote:
My project involves this particular detail where i have to sample a simulated sine wave and get the samples and compare them so as to select a particular length for hanning window.Then it also requires me to experiment with the window size so as to get more efficient data out of the sampled signals. please help me with the sampling part and guide me as to how to perform a hanning window operation on the sampled signal. I have directly used the spectral analysis tool which involves getting a FFT spectrum by a default hanning window setting. But since i have to experiment with the window size and variations, guide me with the sampling part and applying a separate hanning window. Thank you.
What do you mean by i have to sample a simulated sine wave?
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Post your vi if you have trouble with details.
How much do you know about LabVIEW and signal theorie?
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Simultaneous analog output 1k sine wave and data acquisition

Although many topics of simultaneous analog output and input can be found in NI Developer Zone, I have not found a case similar to my project. I'm trying to generate a 1kHz sine wave by using the analog output of NI DAQPad-6070E, and acquire one channel input signal simultaneously. I found most of the examples can not work properly above 100Hz. Any suggestions are welcome. Thank you.
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On Tue, 3 Feb 2004 09:03:07 -0600 (CST), jujian wrote:
>Although many topics of simultaneous analog output and input can be
>found in NI Developer Zone, I have not found a case similar to my
>project. I'm trying to generate a 1kHz sine wave by using the analog
>output of NI DAQPad-6070E, and acquire one channel input signal
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>above 100Hz. Any suggestions are welcome. Thank you.
>
>Jian

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Message Edited by awais.h on 03-30-2010 11:20 PM
Message Edited by awais.h on 03-30-2010 11:21 PM
Solved!
Go to Solution.

Hi
Thanks for the code but I'm afraid it won't work. Like you said the probability of choosing a value that is on both graphs may not happen. This is something that I would like the code to do automatically.
But I did use the previous code posted and made some modifications to it and it seems to work perfectly. Now the next thing is to be able to get just that one value that tells you the first time difference.
Here is what I get using that code.
As you can see from the t Values. I only need the one that is highlighted. If there is a way to filter out the rest it would be great.
I was thinking of a while loop and as soon as the value is higher than 3E-5 it would store the number and stop the loop, but I'm not too familiar with arrays in labview.
Here is the the code modified.
As you can see, it wasn't that big of a modification and it still is your code.
I will keep trying.
Thanks for the help
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FinalShockSpeed.vi ‏55 KB

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AfterPulse.vi ‏51 KB
InSeparateSequence.vi ‏49 KB

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NestedSequences.png ‏26 KB

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Sampling sine wave and saving the samples in an array.

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