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Sampling frequency in psg of shhs1

Dear Professor: The "THOR RES" channel described in the manual, that is, the sampling frequency given by the chest signal, is 10hz. However, when I extracted the data, I found that almost all the" THOR RES" channels in the edf file had about 4 million data points. If we assume that the subject slept for 8 hours at night, So there should be 8*60*60*10= 288,000 or so data points, which is obviously a huge difference from 4 million. If the sampling frequency is 125hz, the data points collected throughout the night should have 8*60*60*125=3.6 million data points, which is very close to 4 million. Is there a mistake in my method? Please correct me. Looking forward to your reply!

I opened a handful of SHHS EDFs and they all showed a THOR RES channel sampled at 10 Hz. Hence, your calculation of 288,000 data points for an 8 hour recording should be correct.

Did you check how many of the 4 million data points have non-missing data for the THOR RES signal output? If I export an EDF to ASCII from EDFbrowser the output has 1 row per the maximum sampling rate, which is 125 Hz in the example above. However, the THOR RES signal only has values output on the tenths-of-a-second rows.

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非常感谢，我发现我是我的方法有误，我最开始使用mne库将edf文件转为了mat文件，数据点就一直是四百万左右，可能是mne库的处理方式问题，目前仍然不清楚，我更换了pyedflib库进行了转换，发现数据点的个数是正常的了，非常感谢您！

Edit: (English) - Thank you very much. I found that my method was wrong. I first used the mne library to convert the edf file to a mat file, and the number of data points was always around four million. It might be a problem with the processing method of the mne library, which is still unclear. I changed to the pyedflib library for conversion and found that the number of data points was normal. Thank you very much!