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Dear Sarah,
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<div class="">Without any additional information, it is difficult to give some recommendations. The only thing that I can think of right now, is that the normalisation operation has some unwanted side effects for you, forcing the normalised output to be ‘flat’.
Could it be that some data points in your original time series are ’NaN’?</div>
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<div class="">Best wishses,</div>
<div class="">Jan-Mathijs</div>
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<div class="">On 1 Feb 2024, at 10:04, Sarah Marbella Grace De Leoz via fieldtrip <<a href="mailto:fieldtrip@science.ru.nl" class="">fieldtrip@science.ru.nl</a>> wrote:</div>
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<div dir="ltr" class="">Greetings,
<div class="">I am currently trying to practice on preprocessing and feature extraction on sleep datasets. I have been following FieldTrip's tutorial on <a href="https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.fieldtriptoolbox.org%2Ftutorial%2Fsleep%2F%23extracting-the-brain-state-and-events-from-continuous-sleep-eeg&data=05%7C02%7Cfieldtrip%40science.ru.nl%7Cdb3ee564584b43660ee008dc26224558%7C084578d9400d4a5aa7c7e76ca47af400%7C1%7C0%7C638427175829105561%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=31Z%2BjtVe6LM7KgnTRT0KVTeXAgNjJGoIwaijR%2FwmF98%3D&reserved=0" originalsrc="https://www.fieldtriptoolbox.org/tutorial/sleep/#extracting-the-brain-state-and-events-from-continuous-sleep-eeg" shash="JpkMvBk8wSmNyt003CKnHoGM2IyEtrqhtEK4dwYIvWWcwWk7M1NOscK3kwJl9ZMR1CSZ/FH3BCkaj/T42ycv2t1GyUlKqlohVtDgpKYAr/hjcLZB/q7T1zdOlnUqtWVnRxo1MvDlE09kmS8goUjIwZgQ+KSOz7HqVn4IfLe572g=" originalsrc="https://www.fieldtriptoolbox.org/tutorial/sleep/#extracting-the-brain-state-and-events-from-continuous-sleep-eeg" shash="LdwiumNuXNQ5T1iU3G0qpemc2nVS4W6ALriNKeiyVRcn+NucoFIg4qA0OHBV11tIr/lSF9RgxPF+0PtGIuBKWY1WKpNLh9OVEAVedkFyyfJIkNDfWv4JNRgHE3Yq3TZWR2pYTSPzUv2pVXAscGFjZWa9e/FuZmEnbKdsc8RZaOw=" target="_blank" class="">this</a> and
seem to be encountering some issues in the section on identifying nREM sleep. After creating a combined channel of the normalized signal of slow-wave activity (SWA) and spindle, ft_databrowser ends up reflecting these 5 channels as flat lines instead of what
is shown in the tutorial. May I know how to fix this?
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<div class="">Thank you in advance!<font color="#888888" class=""><br clear="all" class="">
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<div dir="ltr" class=""><b class=""><font face="trebuchet ms, sans-serif" class="">Sarah Marbella Grace O. De Leoz</font></b>
<div class=""><font face="trebuchet ms, sans-serif" class=""><b class="">BS Physics </b></font></div>
<div class=""><font face="trebuchet ms, sans-serif" class=""><b class="">University of the Philippines</b></font></div>
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https://doi.org/10.1371/journal.pcbi.1002202<br class="">
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