[Mne_analysis] ValueError: The eigenspectrum of the leadfield at this voxel is complex. Consider reducing the rank of the leadfield by using reduce_rank=True.

[Alexandre Gramfort]

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hi Pooja,

can you share a code snippet to replicate this problem?
just a few lines of python with the reading of the data covariance, the forward
and the computation of the make_lcmv so we can investigate.

Alex

On Tue, Sep 3, 2019 at 5:04 AM pooja prabhu <prabhuppooja at gmail.com> wrote:
>
>         External Email - Use Caution
>
> Hai Eric,
> I tried exclude=10 but no luck.
> What else i can change to solve this error?
>
> On Sat, Aug 31, 2019 at 3:35 PM pooja prabhu <prabhuppooja at gmail.com> wrote:
>>
>> Hai group,
>> I encountered the problem while executing the function make_lcmv. The error is ,
>> ValueError: The eigenspectrum of the leadfield at this voxel is complex. Consider reducing the rank of the leadfield by using reduce_rank=True.
>>
>> As recommended i changed included the parameter reduce_rank=True in the function 'make_lcmv', even after that the code gives the same error.
>> I am not sure what is the problem.
>> This work uses 19 channel EEG signals.
>> -------------------------------------
>> Snippet of the code:
>> src= setup_volume_source_space(subj, pos=5.0,mri=aseg_fname, bem=fname_model,mindist=7.0, subjects_dir=subjects_dir)
>> fwd = mne.make_forward_solution(info=raw.info, trans=None, src=src, bem=fname_bem, mindist=2.0, meg=False, eeg=True, n_jobs=1)
>> noise_cov = mne.compute_covariance(epochs, tmin=0, tmax=0.2, method='empirical',
>>                                    rank=None)
>> data_cov = mne.compute_covariance(epochs, tmin=0.2, tmax=epochs.tmax,
>>                                   method='empirical', rank='full')
>> filters = make_lcmv(info=epochs.info, forward=fwd, data_cov=data_cov, reg=0.05,
>>                     noise_cov=noise_cov, pick_ori='max-power',
>>                     weight_norm='nai',reduce_rank=True)
>> ---------------------------------------
>> --
>> Thank You
>> Pooja Prabhu
>>
>
>
> --
> Thank You
> Pooja Prabhu
>
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