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How to get fft for my xy graph????

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Hi i am john,

 

 

I have plotted xy graph for an excel file.

I converted excel file in to text file and saved it as .lvm file. now i need to find fft for that xy graph.

I will attach my text files and my vi. 

Please someone put the program and send me quickly.

I need it urgent.....

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Message 1 of 8
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As has been said before, your x-values are not spaced evenly, thus you need to either resample the data for a linear x ramp or use the unevenly sampled tools. Resampling is probably all you need.

 

 

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Solution
Accepted by topic author johnsasikennedy@gmil.com

Here's one simple way to resample the data for a linear x ramp and make the power spectrum. Modify as needed. (LabVIEW 2011)

 

(luckily you don't need to worry about artifacts because each spectral component contains an integer number of cycles in your data)

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Thank u so much Mr.Alten.

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Message 4 of 8
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Thanks a lot  Mr.Alten. 

 

 

But i need to find fft for the other sample of datas. i cant be able to get it through the vi which u have posted. please check it and send me the new program. Sorry for disturbing u. 

 

PFA

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Message 5 of 8
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Could you please help me and find the error in the previou program for finding fft.

 

PFA

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Message 6 of 8
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Are you constantly reposting the same files over and over again? That is not really helpful, but just wastes our time.

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Message 7 of 8
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You need to remove the column header of the file (it gives you zeroes in the first row).

 

You might want to remove the DC offset.

You might also want to trin the baseline on each side of the intersting part of the data.

 

See how far you get...

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