Not getting expected results with FFT
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
add a comment |
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
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
add a comment |
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
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
python fast-fourier-transform
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
add a comment |
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
add a comment |
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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