# compute\_source\_psd\_epochs 'noisenorm' error **URL:** \ **Category:** Mailing List Archive (read-only)\ **Tags:** list-archive\ **Created:** [September 18, 2018, 9:29pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621 "2018-09-18T21:29:36Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 18, 2018, 9:29pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/1 "2018-09-18T21:29:36Z")
Hi all,    When running compute\_psd\_epochs I get the following error: Traceback (most recent call last):   File "\", line 1, in \   File "/autofs/space/karima\_001/users/alex/software/anaconda2/lib/python2.7/site-packages/mne/minimum\_norm/time\_frequency.py", line 536, in \_compute\_source\_psd\_epochs     prepared=prepared, method\_params=method\_params, verbose=verbose)   File "/autofs/space/karima\_001/users/alex/software/anaconda2/lib/python2.7/site-packages/mne/minimum\_norm/time\_frequency.py", line 46, in \_prepare\_source\_params     K, noise\_norm, vertno, \_ = \_assemble\_kernel(inv, label, method, pick\_ori)   File "\", line 2, in \_assemble\_kernel   File "/autofs/space/karima\_001/users/alex/software/anaconda2/lib/python2.7/site-packages/mne/utils.py", line 729, in verbose     return function(\*args, \*\*kwargs)   File "/autofs/space/karima\_001/users/alex/software/anaconda2/lib/python2.7/site-packages/mne/minimum\_norm/inverse.py", line 679, in \_assemble\_kernel     noise\_norm = inv['noisenorm'][:, None] KeyError: 'noisenorm' My inverse worked to generate the stc so I'm not sure what is going on. Any help would be appreciated. Thanks, Alex Translational NeuroEngineering Laboratory Division of Neurotherapeutics, Department of Psychiatry Massachusetts General Hospital, Martinos Center 149 13th St Charlestown #2301, Boston, MA 02129 -------------- next part -------------- An HTML attachment was scrubbed... URL: [http://mail.nmr.mgh.harvard.edu/pipermail/mne\_analysis/attachments/20180918/16a68fce/attachment.html](http://mail.nmr.mgh.harvard.edu/pipermail/mne_analysis/attachments/20180918/16a68fce/attachment.html) ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 19, 2018, 9:31am UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/2 "2018-09-19T09:31:25Z")
External Email - Use Caution HI Alex, can you check if this error is still present with current master branch? do you only see it when using "MNE" method? Alex ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 19, 2018, 12:41pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/3 "2018-09-19T12:41:09Z")
Hi Alex,    I just pulled the most recent development version of MNE and the error is still occurring. I was originally using python 2.7 but took this impetus to move to python 3.6.5. The MNE version is listed at 0.16.2. Neither python version or the latest pull worked unfortunately, and I am still getting the same error. Thanks, Alex Translational NeuroEngineering Laboratory Division of Neurotherapeutics, Department of Psychiatry Massachusetts General Hospital, Martinos Center 149 13th St Charlestown #2301, Boston, MA 02129 ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 19, 2018, 12:51pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/4 "2018-09-19T12:51:12Z")
External Email - Use Caution ok so please open an issue here [http://github.com/mne-tools/mne-python/issues](http://github.com/mne-tools/mne-python/issues) and provide a full script to replicate the pb using the sample dataset. thanks Alex ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 19, 2018, 8:56pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/5 "2018-09-19T20:56:35Z")
Before I do that, I saw that the inverse\_operator['noisenorm'] property was just an empty list in the example audio inverse. Do you or does anyone know what effect setting that property to an empty list would have? If so, I could just do that. Alex Translational NeuroEngineering Laboratory Division of Neurotherapeutics, Department of Psychiatry Massachusetts General Hospital, Martinos Center 149 13th St Charlestown #2301, Boston, MA 02129 ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 19, 2018, 8:59pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/6 "2018-09-19T20:59:16Z")
Hi Alex, Please feel free to pass by my office, if you want to debug it together. Thanks Sheraz ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 20, 2018, 1:34pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/7 "2018-09-20T13:34:31Z")
I figured it out... it was the prepared = True keyword argument. I hadn't prepared the inverse. It's always the simplest things... thanks for all the help. Alex Translational NeuroEngineering Laboratory Division of Neurotherapeutics, Department of Psychiatry Massachusetts General Hospital, Martinos Center 149 13th St Charlestown #2301, Boston, MA 02129 ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\ **Post date:** [September 20, 2018, 1:38pm UTC](https://mne.discourse.group/t/compute-source-psd-epochs-noisenorm-error/1621/8 "2018-09-20T13:38:40Z")
External Email - Use Caution can we avoid making this mistake next time? we should detect it and provide a good mesage so people don't fall into the trap. can you send us a PR for this? thanks Alex