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## Main Question or Discussion Point

Hello all. I am working on a problem for class that is taking some time data and changing it to frequency data. I am using excel and the fast fourier transform(fft).

I am having a problem graphing the results. I am very new to signal processing.

I am only given the data which is 1024 points long.

I will only ask for help with one because if I figure this one out I can do the rest.

The period is .117. Making the sampline rate 1/.117.

I have the two columns of data here is an example.

The first column is (1*(1/.117)/1024) and the second is the fft values.

pres43 abs imag

0.006643282 162509.4667

0.013286565 388.025981

0.019929847 600.4277992

0.026573129 499.1078937

0.033216412 447.4588355

0.039859694 102.7576392

0.046502976 276.7567742

0.053146259 358.0531147

0.059789541 289.5977569

0.066432823 129.8177899

0.073076105 91.85556182

0.079719388 250.3116294

0.08636267 35.77585877

0.093005952 218.271273

0.099649235 216.1229107

0.106292517 215.5078932

0.112935799 110.6895935

0.119579082 153.2837982

0.126222364 194.9400366

0.132865646 96.83955867

My problems is that I don't know how to graph the values correctly. The graph as it stands is not right. Someone told me that I have to remove the DC zero values? I do not know how to do that and that is why I am asking for help.

Thank you

I am having a problem graphing the results. I am very new to signal processing.

I am only given the data which is 1024 points long.

I will only ask for help with one because if I figure this one out I can do the rest.

The period is .117. Making the sampline rate 1/.117.

I have the two columns of data here is an example.

The first column is (1*(1/.117)/1024) and the second is the fft values.

pres43 abs imag

0.006643282 162509.4667

0.013286565 388.025981

0.019929847 600.4277992

0.026573129 499.1078937

0.033216412 447.4588355

0.039859694 102.7576392

0.046502976 276.7567742

0.053146259 358.0531147

0.059789541 289.5977569

0.066432823 129.8177899

0.073076105 91.85556182

0.079719388 250.3116294

0.08636267 35.77585877

0.093005952 218.271273

0.099649235 216.1229107

0.106292517 215.5078932

0.112935799 110.6895935

0.119579082 153.2837982

0.126222364 194.9400366

0.132865646 96.83955867

My problems is that I don't know how to graph the values correctly. The graph as it stands is not right. Someone told me that I have to remove the DC zero values? I do not know how to do that and that is why I am asking for help.

Thank you