Deleting channel

Discussions
1

Hi everyone!
I was trying to delete some channels from and eeg file but I was not able to make it.

I want to edit the eeg file wich has non eeg channels like ECG and Photic, and I need to export it to EDF (in order to analyse it with neuroscan and other software) ,
I edited channel file and set the unwanted channels as DELETE but I it lead to error when I opened the raw file

In previus post I read that we should not to delete channels from channel file due this lead to error when BS compares channel file with the raw file channels,

So I marked the unwanted channels as MISC, but when I exported the file, unwanted channels was in there too

How can I really delete a channel? and what the "Delete" mark from edit channel menu is for?

Thanks in advance!

ps: actually there is no way to delete a channel in BS right?

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This menu is there to delete the channels from the channel file only. It does not remove the corresponding channels in the data files. If you have data files in the same folder, it will make them unusable. This menu is useful only for users who want to edit the list of electrodes, independently from the data, for most users it is not recommended to use it.

actually there is no way to delete a channel in BS right?

If you have multiple files with different lists of channels, select them all the in Process1 box and use the process "Standardize > Uniform list of channels", you would have the choice to remove the extra channels that are not present in the other files. This corresponds to most of the cases where users would like to delete channels.

For other purposes, we do not recommend removing channels.
If you nevertheless want to do it, you'd have to do it manually by removing the rows corresponding to the channels you want to delete. Edit the F matrix in the data file:
https://neuroimage.usc.edu/brainstorm/Tutorials/Scripting#Custom_processing
https://neuroimage.usc.edu/brainstorm/Tutorials/Scripting#File_structures
This is only possible for imported data, not for links to continuous files.

I want to edit the eeg file wich has non eeg channels like ECG and Photic, and I need to export it to EDF (in order to analyse it with neuroscan and other software) ,

Exporting files imported in Brainstorm to EDF might not be a good idea. EDF files can store only integers, while Brainstorm stores its data in floating point double precision ("double"). The conversion from double to int16 is destructive, similarly to an extra analog to digital conversion, and may alter the dynamics of the signal.
It is recommended using other formats, such as the BrainVision file format, which allows the storage of floating point values (BrainVision Recorder | Brain Products GmbH > Solutions).

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Hi @Francois !
Thanks for the reply!

I think this is the better approach!

I see, I did not know it, thanks for this Info.
:slight_smile: