TFCE threshold cannot compute length after baseline correction

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Hi,

I am applying "permutation_cluster_1samp_test " on my power and itc data.
I am wondering whether I should not use the baseline correction for the
time-frequency data before doing the statistical analysis.

I have attached my code here. When I do the "*apply_baseline*" on each
condition and then do "*permutation_cluster_1samp_test*", I got the
following error, however, if I don't do the "*apply_baseline*" it works
fine. It does not make sense to me why it should not work after applying
the baseline correction.

cond1 = power_avgAll[set_btlc[loc][0]] # <AverageTFR>,
cond.data.shape: (chan X freq X time)
cond2 = power_avgAll[set_btlc[loc][1]]

baseline = (-0.4, -0.3)
cond1.apply_baseline(baseline, mode='mean')
cond2.apply_baseline(baseline, mode='mean')

tfce = dict(start=0, step=.2)
thresh = 0.05
n_permutations = 100000
X = diff = (cond1.data - cond2.data)

T_obs, clusters, cluster_p_values, H0 = \
                    permutation_cluster_1samp_test(X, tfce, n_permutations,
tail=0)

*Error:*
  File
"/Users/MA/anaconda3/lib/python3.6/site-packages/mne/stats/cluster_level.py",
line 316, in _find_clusters
threshold['step'], float)
ValueError: arange: cannot compute length

-Mary
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Hi Mary,

It could be that the baseline is changing the data so that the stopping
threshold in TFCE (which is determined from the data) has changed. Perhaps
what would be useful is to provide is to share a minimal reproducible
script using the sample data so that we can help.

Mainak