FFT - Meaning of coefficients
I am using tsfresh to extract some features of some time series. I would like to have a clear understanding of the fft output. The following is an example of the name of the output of the analysis:
value__fft_coefficient__coeff_90__attr_"angle"
So, I understand the concept of angle, real, abs and angle. However, I do not have clear what 90 means. I know that tsfresh extract the first 100 coefficients, but nothing is referred in the documentation, furthermore, I cannot found an explanation in signal analysis books. I know that it is the 90th coefficient of the fft, but does it represents a frequency?
This question (FFT coefficients question) points out that they are the signal values, but that still does not make it clear what it is, at least for me and from a data science perspective.
Thank you.
python signal-processing fft feature-extraction
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
add a comment |
I am using tsfresh to extract some features of some time series. I would like to have a clear understanding of the fft output. The following is an example of the name of the output of the analysis:
value__fft_coefficient__coeff_90__attr_"angle"
So, I understand the concept of angle, real, abs and angle. However, I do not have clear what 90 means. I know that tsfresh extract the first 100 coefficients, but nothing is referred in the documentation, furthermore, I cannot found an explanation in signal analysis books. I know that it is the 90th coefficient of the fft, but does it represents a frequency?
This question (FFT coefficients question) points out that they are the signal values, but that still does not make it clear what it is, at least for me and from a data science perspective.
Thank you.
python signal-processing fft feature-extraction
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
add a comment |
I am using tsfresh to extract some features of some time series. I would like to have a clear understanding of the fft output. The following is an example of the name of the output of the analysis:
value__fft_coefficient__coeff_90__attr_"angle"
So, I understand the concept of angle, real, abs and angle. However, I do not have clear what 90 means. I know that tsfresh extract the first 100 coefficients, but nothing is referred in the documentation, furthermore, I cannot found an explanation in signal analysis books. I know that it is the 90th coefficient of the fft, but does it represents a frequency?
This question (FFT coefficients question) points out that they are the signal values, but that still does not make it clear what it is, at least for me and from a data science perspective.
Thank you.
python signal-processing fft feature-extraction
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
I am using tsfresh to extract some features of some time series. I would like to have a clear understanding of the fft output. The following is an example of the name of the output of the analysis:
value__fft_coefficient__coeff_90__attr_"angle"
So, I understand the concept of angle, real, abs and angle. However, I do not have clear what 90 means. I know that tsfresh extract the first 100 coefficients, but nothing is referred in the documentation, furthermore, I cannot found an explanation in signal analysis books. I know that it is the 90th coefficient of the fft, but does it represents a frequency?
This question (FFT coefficients question) points out that they are the signal values, but that still does not make it clear what it is, at least for me and from a data science perspective.
Thank you.
python signal-processing fft feature-extraction
python signal-processing fft feature-extraction
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
asked Jan 18 at 23:57
Guido MuscioniGuido Muscioni
164115
164115
add a comment |
add a comment |
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