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Selecting part of signal on the waveform graph

Hello people,

 

I am developing a VI for Heart Rate Variability Analysis. I have plotted a Power spectrum Density plot. I however am not not able to select frequency ranges by sliding bars on the waveform graph. I would like to select a part of the displayed signal and process it (calculate power). It seems simple yet I cant get it. I think ti is to do with property node, but there are so many, I cannot figure out the right one.

Solution please.

 

Thank You

Jas

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Message 1 of 4
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You could try to create your own sliding bars, but I think it will be easier to simply use the built-in Graph Palette which contains a zoom tool to allow you to select ranges of a graph. Once it's zoomed in you can get the zoomed range from the XScale.Range.Minimum and XScale.Range.Maximum.
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Message 2 of 4
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What I really want to do is calculate power for a range of frequencies in FFT.

I have plotted the PSD and extracted the frequency ranges from the PSD array by specifying index values in teh array. Does this sound reasonable???


Also I now need to calulcate power for this range of frequency. How can I do that?

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Message 3 of 4
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You could use graph cursors. I often use them in such cases


Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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Message 4 of 4
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