Sorry if this is incorrect, but it seems that the calculated Frequency Features are inserted always at the beginning of the returned (or rather stored) object always at the beginning such that the real amplitudes of the FFT are added to the end of the dataset. However, the referenced calculated activities are being added in-order in terms of the code, but always at the beginning, so they are reversed. This means that the data being displayed would be incorrectly labeled, if I'm not wrong. I can open a PR with the fix we implemented if people agree that this is wrong. If I'm wrong, I would love to know that as well.
https://github.com/mhoogen/ML4QS/blob/master/Python3Code/Chapter4/FrequencyAbstraction.py#L48
Sorry if this is incorrect, but it seems that the calculated Frequency Features are inserted always at the beginning of the returned (or rather stored) object always at the beginning such that the real amplitudes of the FFT are added to the end of the dataset. However, the referenced calculated activities are being added in-order in terms of the code, but always at the beginning, so they are reversed. This means that the data being displayed would be incorrectly labeled, if I'm not wrong. I can open a PR with the fix we implemented if people agree that this is wrong. If I'm wrong, I would love to know that as well.