Not getting expected results with FFT












0














So I made this virtual car that moves at a velocity that is the sum of three different sine waves (whose individual frequencies I know). I constructed this velocity time graph



Then I perform a FFT on this data and get this amplitude-frequency graph:



The frequencies I input into my waves were 0.033, 0.083, and 0.117, so I'm wondering on how to confirm that these frequencies are showing up on the graph. Am I approaching this problem correctly?



I'm extremely new to FFT and any help/criticism would be much appreciated.










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  • Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
    – Alex J Best
    Nov 30 at 19:51


















0














So I made this virtual car that moves at a velocity that is the sum of three different sine waves (whose individual frequencies I know). I constructed this velocity time graph



Then I perform a FFT on this data and get this amplitude-frequency graph:



The frequencies I input into my waves were 0.033, 0.083, and 0.117, so I'm wondering on how to confirm that these frequencies are showing up on the graph. Am I approaching this problem correctly?



I'm extremely new to FFT and any help/criticism would be much appreciated.










share|cite|improve this question






















  • Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
    – Alex J Best
    Nov 30 at 19:51
















0












0








0







So I made this virtual car that moves at a velocity that is the sum of three different sine waves (whose individual frequencies I know). I constructed this velocity time graph



Then I perform a FFT on this data and get this amplitude-frequency graph:



The frequencies I input into my waves were 0.033, 0.083, and 0.117, so I'm wondering on how to confirm that these frequencies are showing up on the graph. Am I approaching this problem correctly?



I'm extremely new to FFT and any help/criticism would be much appreciated.










share|cite|improve this question













So I made this virtual car that moves at a velocity that is the sum of three different sine waves (whose individual frequencies I know). I constructed this velocity time graph



Then I perform a FFT on this data and get this amplitude-frequency graph:



The frequencies I input into my waves were 0.033, 0.083, and 0.117, so I'm wondering on how to confirm that these frequencies are showing up on the graph. Am I approaching this problem correctly?



I'm extremely new to FFT and any help/criticism would be much appreciated.







python fast-fourier-transform






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share|cite|improve this question











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asked Nov 30 at 19:18









Hanna Haponenko

1




1












  • Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
    – Alex J Best
    Nov 30 at 19:51




















  • Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
    – Alex J Best
    Nov 30 at 19:51


















Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
– Alex J Best
Nov 30 at 19:51






Looks like it is consistent but the range of frequencies being plotted is too large to distinguish your three frequencies. You should try to find how to change the frequency range in whatever software you're using.
– Alex J Best
Nov 30 at 19:51

















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