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EEG Units not converted to Volts

See original GitHub issue

Describe the bug

Hi MNE team, I’m still quite sure what is going on, but i believe that the EEG channels in the attached EDF are not being correctly translated to volts. I’ve opened the file in a number of programs, and the values are different in each.

Steps and/or code to reproduce

the file: unit_testing.zip

import mne
raw = mne.io.read_raw_edf('unit_testing.edf')
some_edf_channels = ['C3','C4']
chan_data = raw.get_data(some_edf_channels)
print(np.sum(np.abs(chan_data))/chan_data.size) #this prints 0.035V, which is too high, it should be 0.000035V

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:7 (4 by maintainers)

github_iconTop GitHub Comments

1reaction
agramfortcommented, Jul 23, 2019

thanks for the clear bug report !

0reactions
bdyettoncommented, Jul 22, 2019

Awesome, working now, thanks 😃

pyedf av in mV: 0.035007964494163435
Wonambi av in mV: 0.03500796449416343
MNE av in V: 3.500796449416343e-05
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