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# labels.append(FEF_label)
# ### Supplementary eye fields
# # Located at caudal end of frontal gyrus and upper part of paracentral sulcus
# label_aparc_names0 = ["G_and_S_paracentral","G_front_sup"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels.append(labels_aparc[labels_aparc_idx[i2]].copy())
# pos1 = temp_labels[0].pos
# pos2 = temp_labels[2].pos
# distm = scipy.spatial.distance.cdist(pos1,pos2)
# # Find the closest points between the 2 ROIs
# l1_idx = np.unique(np.where(distm<np.quantile(distm, 0.0005))[0]) # q chosen to correspond to around 15% of ROI
# l2_idx = np.unique(np.where(distm<np.quantile(distm, 0.005))[1]) # q chosen to correspond to around 10% of ROI
# # Notice that superior frontal gyrus is around 4 times bigger than paracentral
# len(l1_idx)/pos1.shape[0]
# len(l2_idx)/pos2.shape[0]
# # Only use upper part
# z_threshold = 0.06 # visually inspected
# l1_idx = l1_idx[pos1[l1_idx,2] > z_threshold]
# l2_idx = l2_idx[pos2[l2_idx,2] > z_threshold]
# SEF_label_p1 = label_subset(temp_labels[0], l1_idx, "SEF")
# SEF_label_p2 = label_subset(temp_labels[2], l2_idx, "SEF")
# # Combine the 2 parts
# SEF_label = SEF_label_p1.__add__(SEF_label_p2)
# SEF_label.name = SEF_label_p1.name
# # Assign a color
# SEF_label.color = matplotlib.colors.to_rgba("royalblue")
# # Append to final list
# labels.append(SEF_label)
# # Do the same for the right hemisphere
# pos1 = temp_labels[1].pos
# pos2 = temp_labels[3].pos
# distm = scipy.spatial.distance.cdist(pos1,pos2)
# # Find the closest points between the 2 ROIs
# l1_idx = np.unique(np.where(distm<np.quantile(distm, 0.0005))[0]) # q chosen to correspond to around 15% of ROI
# l2_idx = np.unique(np.where(distm<np.quantile(distm, 0.005))[1]) # q chosen to correspond to around 10% of ROI
# # Notice that superior frontal gyrus is around 4 times bigger than paracentral
# len(l1_idx)/pos1.shape[0]
# len(l2_idx)/pos2.shape[0]
# # Only use upper part
# z_threshold = 0.06 # visually inspected
# l1_idx = l1_idx[pos1[l1_idx,2] > z_threshold]
# l2_idx = l2_idx[pos2[l2_idx,2] > z_threshold]
# SEF_label_p1 = label_subset(temp_labels[1], l1_idx, "SEF")
# SEF_label_p2 = label_subset(temp_labels[3], l2_idx, "SEF")
# # Combine the 2 parts
# SEF_label = SEF_label_p1.__add__(SEF_label_p2)
# SEF_label.name = SEF_label_p1.name
# # Assign a color
# SEF_label.color = matplotlib.colors.to_rgba("royalblue")
# # Append to final list
# labels.append(SEF_label)
# ### Posterior cingulate cortex
# label_aparc_names0 = ["G_cingul-Post-dorsal", "G_cingul-Post-ventral"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels.append(labels_aparc[labels_aparc_idx[i2]].copy())
# labels0 = []
# for hem in range(2):
# PCC_p1 = temp_labels[hem]
# for i in range(1,len(temp_labels)//2):
# PCC_p2 = temp_labels[hem+2*i]
# PCC_p1 = PCC_p1.__add__(PCC_p2)
# PCC_p1.name = "PCC-{}".format(PCC_p1.hemi)
# labels0.append(PCC_p1)
# # Combine the 2 hemisphere in 1 label
# labels.append(labels0[0].__add__(labels0[1]))
# ### Medial prefrontal cortex
# # From their schematic it looks like rostral 1/4 of superior frontal gyrus
# label_aparc_names0 = ["G_front_sup"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels0 = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels0 = temp_labels0.split(4, subjects_dir=subjects_dir)[3]
# temp_labels0.name = "mPFC-{}".format(temp_labels0.hemi)
# temp_labels.append(temp_labels0)
# # Combine the 2 hemisphere in 1 label
# labels.append(temp_labels[0].__add__(temp_labels[1]))
# ### Angular gyrus
# label_aparc_names0 = ["G_pariet_inf-Angular"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels.name = "ANG-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# ### Posterior middle frontal gyrus
# label_aparc_names0 = ["G_front_middle"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels = temp_labels.split(2, subjects_dir=subjects_dir)[0]
# temp_labels.name = "PMFG-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# ### Inferior parietal lobule
# # From their parcellation figure seems to be rostral angular gyrus and posterior supramarginal gyrus
# label_aparc_names0 = ["G_pariet_inf-Angular","G_pariet_inf-Supramar"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels.append(labels_aparc[labels_aparc_idx[i2]].copy())
# # Split angular in 2 and get rostral part
# temp_labels[0] = temp_labels[0].split(2, subjects_dir=subjects_dir)[1]
# temp_labels[1] = temp_labels[1].split(2, subjects_dir=subjects_dir)[1]
# # Split supramarginal in 2 and get posterior part
# temp_labels[2] = temp_labels[2].split(2, subjects_dir=subjects_dir)[0]
# temp_labels[3] = temp_labels[3].split(2, subjects_dir=subjects_dir)[0]
# for hem in range(2):
# PCC_p1 = temp_labels[hem]
# for i in range(1,len(temp_labels)//2):
# PCC_p2 = temp_labels[hem+2*i]
# PCC_p1 = PCC_p1.__add__(PCC_p2)
# PCC_p1.name = "IPL-{}".format(PCC_p1.hemi)
# labels.append(PCC_p1)
# ### Orbital gyrus
# # From their figure it seems to correspond to orbital part of inferior frontal gyrus
# label_aparc_names0 = ["G_front_inf-Orbital"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels.name = "ORB-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# ### Middle temporal gyrus
# # From their figure it seems to only be 1/4 of MTG at the 2nd to last caudal part
# label_aparc_names0 = ["G_temporal_middle"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels = temp_labels.split(4, subjects_dir=subjects_dir)[1]
# temp_labels.name = "MTG-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# ### Anterior middle frontal gyrus
# label_aparc_names0 = ["G_front_middle"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels = temp_labels.split(2, subjects_dir=subjects_dir)[1]
# temp_labels.name = "AMFG-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# ### Insula
# label_aparc_names0 = ["G_Ins_lg_and_S_cent_ins","G_insular_short"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels.append(labels_aparc[labels_aparc_idx[i2]].copy())
# for hem in range(2):
# PCC_p1 = temp_labels[hem]
# for i in range(1,len(temp_labels)//2):
# PCC_p2 = temp_labels[hem+2*i]
# PCC_p1 = PCC_p1.__add__(PCC_p2)
# PCC_p1.name = "INS-{}".format(PCC_p1.hemi)
# labels.append(PCC_p1)
# ### (Dorsal) Anterior Cingulate Cortex
# label_aparc_names0 = ["G_and_S_cingul-Ant"]
# temp_labels = []
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels.append(labels_aparc[labels_aparc_idx[i2]].copy())
# temp_labels[-1].name = "ACC-{}".format(temp_labels[-1].hemi)
# # Combine the 2 hemisphere in 1 label
# labels.append(temp_labels[0].__add__(temp_labels[1]))
# ### Supramarginal Gyrus
# label_aparc_names0 = ["G_pariet_inf-Supramar"]
# for i in range(len(label_aparc_names0)):
# labels_aparc_idx = [labels_aparc_names.index(l) for l in labels_aparc_names if l.startswith(label_aparc_names0[i])]
# for i2 in range(len(labels_aparc_idx)):
# temp_labels = labels_aparc[labels_aparc_idx[i2]].copy()
# temp_labels.name = "SUP-{}".format(temp_labels.hemi)
# labels.append(temp_labels)
# print("{} ROIs have been defined".format(len(labels)))
# # # Visualize positions
# # fig = plt.figure()
# # ax = fig.add_subplot(111, projection="3d")
# # for i in range(0,3):
# # temp_pos = temp_labels[i].pos
# # ax.scatter(temp_pos[:,0],temp_pos[:,1],temp_pos[:,2], marker="o", alpha=0.1)
# # # Add to plot
# # ax.scatter(labels[-1].pos[:,0],labels[-1].pos[:,1],labels[-1].pos[:,2], marker="o")
# # # Visualize the labels
# # # temp_l = labels_aparc[labels_aparc_idx[0]]
# # temp_l = labels[-2]
# # l_stc = stc[100].in_label(temp_l)
# # l_stc.vertices
# # l_stc.plot(**surfer_kwargs)
# # Save the annotation file
# with open("custom_aparc2009_Li_et_al_2022.pkl", "wb") as file:
# pickle.dump(labels, file)
# # %% Calculate orthogonalized power envelope connectivity in source space
# # In non-interpolated channels
# # Updated 22/1 - 2021 to use delta = 1/81 and assumption
# # about non-correlated and equal variance noise covariance matrix for channels
# # Load
# with open("custom_aparc2009_Li_et_al_2022.pkl", "rb") as file:
# labels = pickle.load(file)
# label_names = [label.name for label in labels]
# # Define function to estimate PEC
# def PEC_estimation(x, freq_bands, sfreq=200):
# """
# This function takes a source timeseries signal x and performs:
# 1. Bandpass filtering
# 2. Hilbert transform to yield analytical signal
# 3. Compute all to all connectivity by iteratively computing for each pair
# a. Orthogonalization
# b. Computing power envelopes by squaring the signals |x|^2
# c. Log-transform to enhance normality
# d. Pearson's correlation between each pair
# e. Fisher's r-to-z transform to enhance normality
# The code has been optimized by inspiration from MNE-Python's function:
# mne.connectivity.enelope_correlation.
# In MNE-python version < 0.22 there was a bug, but after the fix in 0.22
# the mne function is equivalent to my implementation, although they don't
# use epsilon but gives same result with a RuntimeWarning about log(0)
# IMPORTANT NOTE:
# Filtering introduce artifacts for first and last timepoint
# The values are very low, more than 1e-12 less than the others
# If they are not removed, then they will heavily influence Pearson's
# correlation as it is outlier sensitive
# Inputs:
# x - The signal in source space as np.array with shape (ROIs,Timepoints)
# freq_bands - The frequency bands of interest as a dictionary e.g.
# {"alpha": [8.0, 13.0], "beta": [13.0, 30.0]}
# sfreq - The sampling frequency in Hertz
# Output:
# The pairwise connectivity matrix
# """
# n_roi, n_timepoints = x.shape
# n_freq_bands = len(freq_bands)
# epsilon = 1e-100 # small value to prevent log(0) errors
# # Filter the signal in the different freq bands
# PEC_con0 = np.zeros((n_roi,n_roi,n_freq_bands))
# for fname, frange in freq_bands.items():
# fmin, fmax = [float(interval) for interval in frange]
# signal_filtered = mne.filter.filter_data(x, sfreq, fmin, fmax,
# fir_design="firwin", verbose=0)
# # Filtering on finite signals will yield very low values for first
# # and last timepoint, which can create outliers. E.g. 1e-29 compared to 1e-14
# # Outlier sensitive methods, like Pearson's correlation, is therefore
# # heavily affected and this systematic error is removed by removing
# # the first and last timepoint
# signal_filtered = signal_filtered[:,1:-1]
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# # Hilbert transform
# analytic_signal = scipy.signal.hilbert(signal_filtered)
# # I will use x and y to keep track of orthogonalization
# x0 = analytic_signal
# # Get power envelope
# x0_mag = np.abs(x0)
# # Get scaled conjugate used for orthogonalization estimation
# x0_conj_scaled = x0.conj()
# x0_conj_scaled /= x0_mag
# # Take square power envelope
# PEx = np.square(x0_mag)
# # Take log transform
# lnPEx = np.log(PEx+epsilon)
# # Remove mean for Pearson correlation calculation
# lnPEx_nomean = lnPEx - np.mean(lnPEx, axis=-1, keepdims=True) # normalize each roi timeseries
# # Get std for Pearson correlation calculation
# lnPEx_std = np.std(lnPEx, axis=-1)
# lnPEx_std[lnPEx_std == 0] = 1 # Prevent std = 0 problems
# # Prepare con matrix
# con0 = np.zeros((n_roi,n_roi))
# for roi_r, y0 in enumerate(x0): # for each y0
# # Calculate orthogonalized signal y with respect to x for all x
# # Using y_ort = imag(y*x_conj/|x|)
# # I checked the formula in temp_v3 and it works as intended
# # I want to orthogonalize element wise for each timepoint
# y0_ort = (y0*x0_conj_scaled).imag
# # Here y0_ort.shape = (n_roi, n_timepoints)
# # So y is current roi and the first axis gives each x it is orthogonalized to
# # Take the abs to get power envelope
# y0_ort = np.abs(y0_ort)
# # Prevent log(0) error when calculating y_ort on y
# y0_ort[roi_r] = 1. # this will be 0 zero after mean subtraction
# # Take square power envelope
# PEy = np.square(y0_ort) # squared power envelope
# # Take log transform
# lnPEy = np.log(PEy+epsilon)
# # Remove mean for pearson correlation calculation
# lnPEy_nomean = lnPEy - np.mean(lnPEy, axis=-1, keepdims=True)
# # Get std for Pearson correlation calculation
# lnPEy_std = np.std(lnPEy, axis=-1)
# lnPEy_std[lnPEy_std == 0] = 1.
# # Pearson correlation is expectation of X_nomean * Y_nomean for each time-series divided with standard deviations
# PEC = np.mean(lnPEx_nomean*lnPEy_nomean, axis=-1)
# PEC /= lnPEx_std
# PEC /= lnPEy_std
# con0[roi_r] = PEC
# # The con0 connectivity matrix should be read as correlation between
# # orthogonalized y (row number) and x (column number)
# # It is not symmetrical, as cor(roi2_ort, roi1) is not cor(roi1_ort, roi2)
# # To make it symmetrical the average of the absolute correlation
# # of the 2 possibilities for each pair are taken
# con0 = np.abs(con0)
# con0 = (con0.T+con0)/2.
# # Fisher's z transform - which is equivalent to arctanh
# con0 = np.arctanh(con0)
# # The diagonal is not 0 as I wanted to avoid numerical errors with log(0)
# # and used a small epsilon value. Thus the diagonal is explicitly set to 0
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# # Save to array
# PEC_con0[:,:,list(freq_bands.keys()).index(fname)] = con0
# return PEC_con0
# # Prepare variables
# Freq_Bands = {"delta": [1.25, 4.0],
# "theta": [4.0, 8.0],
# "alpha": [8.0, 13.0],
# "beta": [13.0, 30.0],
# "gamma": [30.0, 49.0]}
# n_freq_bands = len(Freq_Bands)
# n_roi = len(labels)
# # Get current time
# c_time1 = time.localtime()
# c_time1 = time.strftime("%a %d %b %Y %H:%M:%S", c_time1)
# print(c_time1)
# # PEC analysis
# PEC_data_list = [0]*n_subjects
# STCs_list = [0]*n_subjects
# # Using inverse operator as generator interferes with concurrent processes
# # If I run it for multiple subjects I run out of ram
# # Thus concurrent processes are used inside the for loop
# def PEC_analysis(input_args): # iterable epoch number and corresponding ts
# i2, ts = input_args
# # Estimate PEC
# PEC_con0 = PEC_estimation(ts, Freq_Bands, sfreq)
# print("Finished {} out of {} epochs".format(i2+1,n_epochs))
# return i2, PEC_con0, ts
# for i in range(n_subjects):
# n_epochs, n_ch, n_timepoints = source_epochs[i].get_data().shape
# # Use different forward solutions depending on number of channels
# cur_subject_id = Subject_id[i]
# fwd = fwds[i]
# # Using assumption about equal variance and no correlations I make a diagonal matrix
# # Using the default option for 0.2µV std for EEG data
# noise_cov = mne.make_ad_hoc_cov(source_epochs[i].info, None)
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# # Make inverse operator
# # Using default depth parameter = 0.8 and free orientation (loose = 1)
# inverse_operator = mne.minimum_norm.make_inverse_operator(source_epochs[i].info,
# fwd, noise_cov,
# loose = 1, depth = 0.8,
# verbose = 0)
# src_inv = inverse_operator["src"]
# # Compute inverse solution and retrieve time series for each label
# # Preallocate memory
# label_ts = np.full((n_epochs,len(labels),n_timepoints),np.nan)
# # Define regularization
# snr = 9 # Zhang et al, 2020 used delta = 1/81, which is inverse SNR and correspond to lambda2
# # A for loop is used for each label due to memory issues when doing all labels at the same time
# for l in range(len(labels)):
# stc = mne.minimum_norm.apply_inverse_epochs(source_epochs[i],inverse_operator,
# lambda2 = 1/(snr**2),
# label = labels[l],
# pick_ori = "vector",
# return_generator=False,
# method = "MNE", verbose = 0)
# # Use PCA to reduce the 3 orthogonal directions to 1 principal direction with max power
# # There can be ambiguity about the orientation, thus the one that
# # is pointing most "normal", i.e. closest 90 degrees to the skull is used
# stc_pca = [0]*len(stc)
# for ep in range(n_epochs):
# stc_pca[ep], pca_dir = stc[ep].project(directions="pca", src=src_inv)
# # Get mean time series for the whole label
# temp_label_ts = mne.extract_label_time_course(stc_pca, labels[l], src_inv, mode="mean_flip",
# return_generator=False, verbose=0)
# # Save to array
# label_ts[:,l,:] = np.squeeze(np.array(temp_label_ts))
# print("Finished estimating STC for {} out of {} ROIs".format(l+1,len(labels)))
# # Free up memory
# del stc
# # Prepare variables
# sfreq=source_epochs[i].info["sfreq"]
# n_epochs = len(source_epochs[i])
# # Estimate the pairwise PEC for each epoch
# PEC_con_subject = np.zeros((n_epochs,n_roi,n_roi,n_freq_bands))
# stcs0 = np.zeros((n_epochs,n_roi,int(sfreq)*4)) # 4s epochs
# # Make list of arguments to pass into PEC_analysis using the helper func
# args = []
# for i2 in range(n_epochs):
# args.append((i2,label_ts[i2]))
# with concurrent.futures.ProcessPoolExecutor(max_workers=16) as executor:
# for i2, PEC_result, stc_result in executor.map(PEC_analysis, args): # Function and arguments
# PEC_con_subject[i2] = PEC_result
# stcs0[i2] = stc_result
# # Save to list
# PEC_data_list[i] = PEC_con_subject # [subject](epoch,ch,ch,freq)
# STCs_list[i] = stcs0 # [subject][epoch,roi,timepoint]
# # Print progress
# print("Finished {} out of {} subjects".format(i+1,n_subjects))
# # Get current time
# c_time2 = time.localtime()
# c_time2 = time.strftime("%a %d %b %Y %H:%M:%S", c_time2)
# print("Started", c_time1, "\nFinished",c_time2)
# with open(Feature_savepath+"PEC_each_epoch_drop_interpol_ch_fix_snr.pkl", "wb") as file:
# pickle.dump(PEC_data_list, file)
# with open(Feature_savepath+"STCs_each_epoch_drop_interpol_ch_fix_snr.pkl", "wb") as file:
# pickle.dump(STCs_list, file)
# # # # Load
# # with open(Feature_savepath+"PEC_each_epoch_drop_interpol_ch_fix_snr.pkl", "rb") as file:
# # PEC_data_list = pickle.load(file)
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# # with open(Feature_savepath+"STCs_each_epoch_drop_interpol_ch_fix_snr.pkl", "rb") as file:
# # STCs_list = pickle.load(file)
# # Average over eye status
# eye_status = list(source_epochs[0].event_id.keys())
# n_eye_status = len(eye_status)
# pec_data = np.zeros((n_subjects,n_eye_status,n_roi,n_roi,n_freq_bands))
# for i in range(n_subjects):
# # Get indices for eyes open and closed
# EC_index = source_epochs[i].events[:,2] == 1
# EO_index = source_epochs[i].events[:,2] == 2
# # Average over the indices and save to array
# pec_data[i,0] = np.mean(PEC_data_list[i][EC_index], axis=0)
# pec_data[i,1] = np.mean(PEC_data_list[i][EO_index], axis=0)
# # Only use the lower diagonal as the diagonal should be 0 (or very small due to numerical errors)
# # And it is symmetric
# for f in range(n_freq_bands):
# pec_data[i,0,:,:,f] = np.tril(pec_data[i,0,:,:,f],k=-1)
# pec_data[i,1,:,:,f] = np.tril(pec_data[i,1,:,:,f],k=-1)
# # Also save as dataframe format for feature selection
# # Convert to Pandas dataframe
# # The dimensions will each be a column with numbers and the last column will be the actual values
# arr = np.column_stack(list(map(np.ravel, np.meshgrid(*map(np.arange, pec_data.shape), indexing="ij"))) + [pec_data.ravel()])
# pec_data_df = pd.DataFrame(arr, columns = ["Subject_ID", "Eye_status", "chx", "chy", "Freq_band", "Value"])
# # Change from numerical coding to actual values
# eye_status = list(source_epochs[0].event_id.keys())
# freq_bands_name = list(Freq_Bands.keys())
# label_names = [label.name for label in labels]
# index_values = [Subject_id,eye_status,label_names,label_names,freq_bands_name]
# for col in range(len(index_values)):
# col_name = pec_data_df.columns[col]
# for shape in range(pec_data.shape[col]): # notice not dataframe but the array
# pec_data_df.loc[pec_data_df.iloc[:,col] == shape,col_name]\
# = index_values[col][shape]
# # Add group status
# Group_status = np.array(["CTRL"]*len(pec_data_df["Subject_ID"]))
# Group_status[np.array([i in cases for i in pec_data_df["Subject_ID"]])] = "PTSD"
# # Add to dataframe
# pec_data_df.insert(3, "Group_status", Group_status)
# # Remove all diagonal and upper-matrix entries by removing zeros
# pec_data_df = pec_data_df.iloc[pec_data_df["Value"].to_numpy().nonzero()]
# # Save df
# pec_data_df.to_pickle(os.path.join(Feature_savepath,"pec_data_drop_interpol_ch_df.pkl"))
# # %% Sparse clustering of PEC for subtyping PTSD group
# # They did it for both eye status together, so all data in one matrix
# # Load PEC df
# # pec_data_df = pd.read_pickle(os.path.join(Feature_savepath,"pec_data_df.pkl"))
# pec_data_df = pd.read_pickle(os.path.join(Feature_savepath,"pec_data_drop_interpol_ch_df.pkl"))
# # Convert to wide format
# # Make function to add measurement column for indexing
# def add_measurement_column(df, measurement = "Text"):
# dummy_variable = [measurement]*df.shape[0]
# df.insert(1, "Measurement", dummy_variable)
# return df
# # Make function to convert column tuple to string
# def convertTupleHeader(header):
# header = list(header)
# str = "_".join(header)
# return str
# # Prepare overall dataframe
# PEC_df = pd.DataFrame(Subject_id, columns = ["Subject_ID"])
# # Add PEC
# pec_data_df = add_measurement_column(pec_data_df, "PEC")
# temp_df = pec_data_df.pivot_table(index="Subject_ID",columns=["Measurement",
# "Eye_status", "chx", "chy",
# "Freq_band"], dropna=True,
# values="Value").reset_index(drop=True)
# # check NaN is properly dropped and subject index is correct
# assert pec_data_df.shape[0] == np.prod(temp_df.shape)
# test1 = pec_data_df.iloc[np.random.randint(n_subjects),:]
# assert test1["Value"] ==\
# temp_df[test1[1]][test1[2]][test1[3]][test1[5]][test1[6]][Subject_id.index(test1[0])]
# # Fix column names
# temp_df.columns = [convertTupleHeader(temp_df.columns[i]) for i in range(len(temp_df.columns))]
# PEC_df = pd.concat([PEC_df,temp_df], axis=1)
# # Add group status
# Groups = ["CTRL", "PTSD"]
# Group_status = np.array([0]*PEC_df.shape[0]) # CTRL = 0
# Group_status[np.array([i in cases for i in PEC_df["Subject_ID"]])] = 1 # PTSD = 1
# PEC_df.insert(1, "Group_status", Group_status)
# # Only use PTSD patient group
# PEC_df2 = PEC_df.loc[PEC_df["Group_status"]==1,:]
# Subject_info_cols = ["Subject_ID","Group_status"]
# # Use gridsearch and permutations to estimate gap statistic and use it to
# # determine number of clusters and sparsity s
# # I will use 100 permutations and test 2 to 6 clusters as Zhang 2020
# # Error when trying to determine Gap statistic for 1 cluster? Also in R package
# max_clusters = 6
# n_sparsity_feat = 20
# perm_res = []
# for k in range(1,max_clusters):
# # Cannot permute with 1 cluster
# n_clusters = k+1
# x = np.array(PEC_df2.copy().drop(Subject_info_cols, axis=1))
# perm = pysparcl.cluster.permute_modified(x, k=n_clusters, verbose=True,
# nvals=n_sparsity_feat, nperms=100)
# perm_res.append(perm)
# # Save the results
# with open(Feature_savepath+"PEC_drop_interpol_ch_kmeans_perm.pkl", "wb") as file:
# pickle.dump(perm_res, file)
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# # # Load
# # with open(Feature_savepath+"PEC_drop_interpol_ch_kmeans_perm.pkl", "rb") as file:
# # perm_res = pickle.load(file)
# # Convert results to array
# perm_res_arr = np.zeros((len(perm_res)*n_sparsity_feat,4))
# for i in range(len(perm_res)):
# _, gaps, sdgaps, wbounds, _ = perm_res[i].values()
# for i2 in range(n_sparsity_feat):
# perm_res_arr[20*i+i2,0] = i+2 # cluster size
# perm_res_arr[20*i+i2,1] = gaps[i2] # gap statistic
# perm_res_arr[20*i+i2,2] = sdgaps[i2] # gap statistic std
# perm_res_arr[20*i+i2,3] = wbounds[i2] # sparsity feature s
# # For each sparsity s, determine best k using one-standard-error criterion
# # Meaning the cluster and sparsity is chosen for the smallest value of k for a fixed s
# # that fulfill Gap(k) >= Gap(k+1)-std(k+1)
# def one_standard_deviation_search(gaps, std):
# best_gaps = np.argmax(gaps)
# current_gaps = gaps[best_gaps]
# current_std = std[best_gaps]
# current_gaps_idx = best_gaps
# while (gaps[current_gaps_idx-1] >= current_gaps - current_std):
# if current_gaps_idx == 0:
# break
# else:
# current_gaps_idx -= 1
# current_gaps = gaps[current_gaps_idx]
# current_std = std[current_gaps_idx]
# out = current_gaps, current_std, current_gaps_idx
# return out
# best_ks = np.zeros((n_sparsity_feat, 2))
# all_s = np.unique(perm_res_arr[:,3])
# plt.figure(figsize=(12,12))
# for i2 in range(n_sparsity_feat):
# current_s = all_s[i2]
# gaps = perm_res_arr[perm_res_arr[:,3] == current_s,1]
# std = perm_res_arr[perm_res_arr[:,3] == current_s,2]
# _, _, idx = one_standard_deviation_search(gaps, std)
# # Save to array
# best_ks[i2,0] = current_s
# best_ks[i2,1] = perm_res_arr[perm_res_arr[:,3] == current_s,0][idx]
# # Plot gap
# plt.errorbar(perm_res_arr[perm_res_arr[:,3] == current_s,0].astype("int"),
# gaps, yerr=std, capsize=5, label = np.round(current_s,3))
# plt.title("Gap statistic for different fixed s")
# plt.legend(loc=1)
# plt.xlabel("Number of clusters")
# plt.ylabel("Gap statistic")
# best_k = int(scipy.stats.mode(best_ks[:,1])[0])
# # Determine s using fixed k as lowest s within 1 std of max gap statistic
# # According to Witten & Tibshirani, 2010
# best_gaps_idx = np.argmax(perm_res_arr[perm_res_arr[:,0] == best_k,1])
# best_gaps = perm_res_arr[perm_res_arr[:,0] == best_k,1][best_gaps_idx]
# best_gaps_std = perm_res_arr[perm_res_arr[:,0] == best_k,2][best_gaps_idx]
# one_std_crit = perm_res_arr[perm_res_arr[:,0] == best_k,1]>=best_gaps-best_gaps_std
# best_s = np.array([perm_res_arr[perm_res_arr[:,0] == best_k,3][one_std_crit][0]])
# # Perform clustering with k clusters
# x = np.array(PEC_df2.copy().drop(Subject_info_cols, axis=1))
# sparcl = pysparcl.cluster.kmeans(x, k=best_k, wbounds=best_s)[0]
# # Save the results
# with open(Feature_savepath+"PEC_drop_interpol_ch_sparse_kmeans.pkl", "wb") as file:
# pickle.dump(sparcl, file)
# # Get overview of the features chosen and summarize feature type with countplot
# nonzero_idx = sparcl["ws"].nonzero()
# sparcl_features = PEC_df2.copy().drop(Subject_info_cols, axis=1).columns[nonzero_idx]
# # Prepare variables
# Freq_Bands = {"delta": [1.25, 4.0],
# "theta": [4.0, 8.0],
# "alpha": [8.0, 13.0],
# "beta": [13.0, 30.0],
# "gamma": [30.0, 49.0]}
# n_freq_bands = len(Freq_Bands)
# eye_status = list(source_epochs[0].event_id.keys())
# n_eye_status = len(eye_status)
# sparcl_feat = []
# sparcl_feat_counts = []
# for e in range(n_eye_status):
# ee = eye_status[e]
# for f in range(n_freq_bands):
# ff = list(Freq_Bands.keys())[f]
# temp_feat = sparcl_features[sparcl_features.str.contains(("_"+ee))]
# temp_feat = temp_feat[temp_feat.str.contains(("_"+ff))]
# # Save to list
# sparcl_feat.append(temp_feat)
# sparcl_feat_counts.append(["{}_{}".format(ee,ff), len(temp_feat)])
# # Convert the list to dataframe to use in countplot
# sparcl_feat_counts_df = pd.DataFrame(columns=["Eye_status", "Freq_band"])
# for i in range(len(sparcl_feat_counts)):
# # If this feature type does not exist, then skip it
# if sparcl_feat_counts[i][1] == 0:
# continue
# ee, ff = sparcl_feat_counts[i][0].split("_")
# counts = sparcl_feat_counts[i][1]
# temp_df = pd.DataFrame({"Eye_status":np.repeat(ee,counts),
# "Freq_band":np.repeat(ff,counts)})
# sparcl_feat_counts_df = sparcl_feat_counts_df.append(temp_df, ignore_index=True)
# # Fix Freq_band categorical order
# cat_type = pd.CategoricalDtype(categories=list(Freq_Bands.keys()), ordered=True)
# sparcl_feat_counts_df["Freq_band"] = sparcl_feat_counts_df["Freq_band"].astype(cat_type)
# plt.figure(figsize=(8,8))
# g = sns.countplot(y="Freq_band", hue="Eye_status", data=sparcl_feat_counts_df)
# plt.title("PEC Sparse K-means features")
# plt.xlabel("Number of non-zero weights")
# plt.ylabel("Frequency Band")
# # %% Functional connectivity in source space
# # MNE implementation of PLV and wPLI is phase across trials(epochs), e.g. for ERPs
# # I'll use my own manually implemented PLV and wPLI across time and then average across epochs
# # Notice that the new MNE-connectivity library now also takes phase across time
# sfreq = final_epochs[0].info["sfreq"]
# # error when using less than 5 cycles for spectrum estimation
# # 1Hz too low with epoch length of 4, thus I changed the fmin to 1.25 for delta
# Freq_Bands = {"delta": [1.25, 4.0],
# "theta": [4.0, 8.0],
# "alpha": [8.0, 13.0],
# "beta": [13.0, 30.0],
# "gamma": [30.0, 49.0]}
# n_freq_bands = len(Freq_Bands)
# freq_centers = np.array([2.5,6,10.5,21.5,40])
# # Convert to tuples for the mne function
# fmin=tuple([list(Freq_Bands.values())[f][0] for f in range(len(Freq_Bands))])
# fmax=tuple([list(Freq_Bands.values())[f][1] for f in range(len(Freq_Bands))])
# # Make linspace array for morlet waves
# freq_centers = np.arange(fmin[0],fmax[-1]+0.25,0.25)
# # Prepare Morlets
# morlets = mne.time_frequency.tfr.morlet(sfreq,freq_centers,n_cycles=3)
# # Make freqs array for indexing
# freqs0 = [0]*n_freq_bands
# for f in range(n_freq_bands):
# freqs0[f] = freq_centers[(freq_centers>=fmin[f]) & (freq_centers<=fmax[f])]
# # The in-built connectivity function gives an (n_channel, n_channel, freqs output
# # For loop over subject ID and eye status is implemented
# n_subjects = len(Subject_id)
# eye_status = list(final_epochs[0].event_id.keys())
# n_eye_status = len(eye_status)
# ch_names = final_epochs[0].info["ch_names"]
# # Load source labels
# with open("custom_aparc2009_Li_et_al_2022.pkl", "rb") as file:
# labels = pickle.load(file)
# label_names = [label.name for label in labels]
# n_sources = len(label_names)
# # Connectivity methods
# connectivity_methods = ["coh","imcoh","plv","wpli"]
# n_con_methods=len(connectivity_methods)
# # Number of pairwise ch connections
# n_ch_connections = scipy.special.comb(n_sources,2, exact=True, repetition=False)
# # Load source time series
# with open(Feature_savepath+"STCs_each_epoch_drop_interpol_ch_fix_snr.pkl", "rb") as file:
# STCs_list = pickle.load(file)
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# # I made my own slightly-optimized PLV & WPLI function
# # Version 2 based on Filter + Hilbert instead of Morlets
# def calculate_PLV_WPLI_across_time(data):
# n_ch, n_time0 = data.shape
# x = data.copy()
# # Filter the signal in the different freq bands
# con_array0 = np.zeros((2,n_ch,n_ch,n_freq_bands))
# # con_array0[con_array0==0] = np.nan
# for fname, frange in Freq_Bands.items():
# fmin, fmax = [float(interval) for interval in frange]
# signal_filtered = mne.filter.filter_data(x, sfreq, fmin, fmax,
# fir_design="firwin", verbose=0)
# # Filtering on finite signals will yield very low values for first
# # and last timepoint, which can create outliers. E.g. 1e-29 compared to 1e-14
# # This systematic error is removed by removing the first and last timepoint
# signal_filtered = signal_filtered[:,1:-1]
# # Hilbert transform to get complex signal
# analytic_signal = scipy.signal.hilbert(signal_filtered)
# # Calculate for the lower diagnonal only as it is symmetric
# for ch_r in range(n_ch):
# for ch_c in range(n_ch):
# if ch_r>ch_c:
# # =========================================================================
# # PLV over time correspond to mean across time of the absolute value of
# # the circular length of the relative phases. So PLV will be 1 if
# # the phases of 2 signals maintain a constant lag
# # In equational form: PLV = 1/N * |sum(e^i(phase1-phase2))|
# # In code: abs(mean(exp(1i*phase_diff)))
# # =========================================================================
# # The real part correspond to the amplitude and the imaginary part can be used to calculate the phase
# phase_diff = np.angle(analytic_signal[ch_r])-np.angle(analytic_signal[ch_c])
# # Convert phase difference to complex part i(phase1-phase2)
# phase_diff_im = 0*phase_diff+1j*phase_diff
# # Take the exponential, then the mean followed by absolute value
# PLV = np.abs(np.mean(np.exp(phase_diff_im)))
# # Save to array
# con_array0[0,ch_r,ch_c,list(Freq_Bands.keys()).index(fname)] = PLV
# # =========================================================================
# # PLI over time correspond to the sign of the sine of relative phase
# # differences. So PLI will be 1 if one signal is always leading or
# # lagging behind the other signal. But it is insensitive to changes in
# # relative phase, as long as it is the same signal that leads.
# # If 2 signals are almost in phase, they might shift between lead/lag
# # due to small fluctuations from noise. This would lead to unstable
# # estimation of "phase" synchronisation.
# # The wPLI tries to correct for this by weighting the PLI with the
# # magnitude of the lag, to attenuate noise sources giving rise to
# # near zero phase lag "synchronization"
# # In equational form: WPLI = |E{|phase_diff|*sign(phase_diff)}| / E{|phase_diff|}
# # =========================================================================
# # Calculate the magnitude of phase differences
# phase_diff_mag = np.abs(np.sin(phase_diff))
# # Calculate the signed phase difference (PLI)
# sign_phase_diff = np.sign(np.sin(phase_diff))
# # Calculate the nominator (abs and average across time)
# WPLI_nominator = np.abs(np.mean(phase_diff_mag*sign_phase_diff))
# # Calculate denominator for normalization
# WPLI_denom = np.mean(phase_diff_mag)
# # Calculate WPLI
# WPLI = WPLI_nominator/WPLI_denom
# # Save to array
# con_array0[1,ch_r,ch_c,list(Freq_Bands.keys()).index(fname)] = WPLI
# return con_array0
# # Pre-allocatate memory
# con_data = np.zeros((n_con_methods,n_subjects,n_eye_status,n_sources,n_sources,n_freq_bands))
# n_epochs_matrix = np.zeros((n_subjects,n_eye_status))
# # Get current time
# c_time = time.localtime()
# c_time = time.strftime("%H:%M:%S", c_time)
# print(c_time)
# def connectivity_estimation(i):
# con_data0 = np.zeros((n_con_methods,n_eye_status,n_sources,n_sources,n_freq_bands))
# con_data0[con_data0==0] = np.nan
# n_epochs_matrix0 = np.zeros((n_eye_status))
# for e in range(n_eye_status):
# ee = eye_status[e]
# eye_idx = final_epochs[i].events[:,2] == e+1 # EC = 1 and EO = 2
# # Get source time series
# temp_STC = STCs_list[i][eye_idx]
# # Calculate the coherence and ImgCoh for the given subject and eye status
# con, freqs, times, n_epochs, n_tapers = spectral_connectivity(
# temp_STC, method=connectivity_methods[0:2],
# mode="multitaper", sfreq=sfreq, fmin=fmin, fmax=fmax,
# faverage=True, verbose=0)
# # Save the results in array
# con_data0[0,e,:,:,:] = con[0] # coherence
# con_data0[1,e,:,:,:] = np.abs(con[1]) # Absolute value of ImgCoh to reflect magnitude of ImgCoh
# # Calculate PLV and wPLI for each epoch and then average
# n_epochs0 = temp_STC.shape[0]
# con_data1 = np.zeros((len(connectivity_methods[2:]),n_epochs0,n_sources,n_sources,n_freq_bands))
# for epoch in range(n_epochs0):
# # First the data is retrieved and epoch axis dropped
# temp_data = temp_STC[epoch,:,:]
# # PLV and WPLI value is calculated across timepoints in each freq band
# PLV_WPLI_con = calculate_PLV_WPLI_across_time(temp_data)
# # Save results
# con_data1[0,epoch,:,:,:] = PLV_WPLI_con[0] # phase locking value
# con_data1[1,epoch,:,:,:] = PLV_WPLI_con[1] # weighted phase lag index
# # Take average across epochs for PLV and wPLI
# con_data2 = np.mean(con_data1,axis=1)
# # Save to final array
# con_data0[2,e,:,:,:] = con_data2[0] # phase locking value
# con_data0[3,e,:,:,:] = con_data2[1] # weighted phase lag index
# n_epochs_matrix0[e] = n_epochs
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# print("{} out of {} finished".format(i+1,n_subjects))
# return i, con_data0, n_epochs_matrix0
# with concurrent.futures.ProcessPoolExecutor(max_workers=16) as executor:
# for i, con_result, n_epochs_mat in executor.map(connectivity_estimation, range(n_subjects)): # Function and arguments
# con_data[:,i,:,:,:,:] = con_result
# n_epochs_matrix[i] = n_epochs_mat
# # Get current time
# c_time = time.localtime()
# c_time = time.strftime("%H:%M:%S", c_time)
# print(c_time)
# # Save the results
# np.save(Feature_savepath+"Source_drop_interpol_ch_connectivity_measures_data.npy", con_data) # (con_measure,subject,eye,ch,ch,freq)
# # Also save as dataframe format for feature selection
# # Convert to Pandas dataframe
# # The dimensions will each be a column with numbers and the last column will be the actual values
# arr = np.column_stack(list(map(np.ravel, np.meshgrid(*map(np.arange, con_data.shape), indexing="ij"))) + [con_data.ravel()])
# con_data_df = pd.DataFrame(arr, columns = ["Con_measurement", "Subject_ID", "Eye_status", "chx", "chy", "Freq_band", "Value"])
# # Change from numerical coding to actual values
# eye_status = list(final_epochs[0].event_id.keys())
# freq_bands_name = list(Freq_Bands.keys())
# index_values = [connectivity_methods,Subject_id,eye_status,label_names,label_names,freq_bands_name]
# for col in range(len(index_values)):
# col_name = con_data_df.columns[col]
# for shape in range(con_data.shape[col]): # notice not dataframe but the array
# con_data_df.loc[con_data_df.iloc[:,col] == shape,col_name]\
# = index_values[col][shape]
# # Add group status
# Group_status = np.array(["CTRL"]*len(con_data_df["Subject_ID"]))
# Group_status[np.array([i in cases for i in con_data_df["Subject_ID"]])] = "PTSD"
# # Add to dataframe
# con_data_df.insert(3, "Group_status", Group_status)
# # Remove all diagonal and upper-matrix entries
# con_data_df = con_data_df.iloc[con_data_df["Value"].to_numpy().nonzero()]
# # Save df
# con_data_df.to_pickle(os.path.join(Feature_savepath,"con_data_source_drop_interpol_df.pkl"))
# # %% Estimate Granger's Causality in source space
# # Load source labels
# with open("custom_aparc2009_Li_et_al_2022.pkl", "rb") as file:
# labels = pickle.load(file)
# label_names = [label.name for label in labels]
# n_sources = len(label_names)
# # Load source time series
# with open(Feature_savepath+"STCs_each_epoch_drop_interpol_ch_fix_snr.pkl", "rb") as file:
# STCs_list = pickle.load(file)
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# # Granger's causality might be influenced by volume conduction, thus working with CSD might be beneficial
# # But since I already used source modelling to alleviate this problem I will not apply CSD
# # Barrett et al, 2012 also do not apply CSD on source GC
# # GC assumes stationarity, thus I will test for stationarity using ADF test
# # The null hypothesis of ADF is that it has unit root, i.e. is non-stationary
# # I will test how many can reject the null hypothesis, i.e. are stationary
# # Due to the low numerical values in STC the ADF test is unstable, thus I multiply it to be around 1e0
# stationary_test_arr = [0]*n_subjects
# n_tests = [0]*n_subjects
# for i in range(n_subjects):
# # Get data
# data_arr = STCs_list[i]
# # Get shape
# n_epochs, n_channels, n_timepoints = data_arr.shape
# # Create array for indices to print out progress
# ep_progress_idx = np.arange(n_epochs//5,n_epochs,n_epochs//5)
# # Calculate number of tests performed for each subject
# n_tests[i] = n_epochs*n_channels
# # Prepare empty array (with 2's as 0 and 1 will be used)
# stationary_test_arr0 = np.zeros((n_epochs,n_channels))+2 # make array of 2's
# for ep in range(n_epochs):
# for c in range(n_channels):
# ADF = adfuller(data_arr[ep,c,:]*1e14) # multilying with a constant does not change ADF, but helps against numerical instability
# p_value = ADF[1]
# if p_value < 0.05:
# stationary_test_arr0[ep,c] = True # Stationary set to 1
# else:
# stationary_test_arr0[ep,c] = False # Non-stationary set to 0
# # Print partial progress
# if len(np.where(ep_progress_idx==ep)[0]) > 0:
# print("Finished epoch number: {} out of {}".format(ep,n_epochs))
# # Indices that were not tested
# no_test_idx = np.where(stationary_test_arr0==2)[0]
# if len(no_test_idx) > 0:
# print("An unexpected error occurred and {} was not tested".format(no_test_idx))
# # Save to list
# stationary_test_arr[i] = stationary_test_arr0
# # Print progress
# print("Finished subject {} out of {}".format(i+1,n_subjects))
# with open(Stat_savepath+"Source_drop_interpol_GC_stationarity_tests.pkl", "wb") as filehandle:
# # The data is stored as binary data stream
# pickle.dump(stationary_test_arr, filehandle)
# # I used a threshold of 0.05
# # This means that on average I would expect 5% false positives among the tests that showed significance for stationarity
# ratio_stationary = [0]*n_subjects
# for i in range(n_subjects):
# # Ratio of tests that showed stationarity
# ratio_stationary[i] = np.sum(stationary_test_arr[i])/n_tests[i]
# print("Ratio of stationary time series: {0:.3f}".format(np.mean(ratio_stationary))) # 88%
# # The pre-processing have already ensured that most of the data fulfills the stationarity assumption.
# # Divide the data into eyes closed and open
# ch_names = label_names
# n_channels = len(ch_names)
# STC_eye_data = []
# for i in range(n_subjects):
# # Get index for eyes open and eyes closed
# EC_index = final_epochs[i].events[:,2] == 1
# EO_index = final_epochs[i].events[:,2] == 2
# # Get the data
# EC_epoch_data = STCs_list[i][EC_index,:,:] # eye index
# EO_epoch_data = STCs_list[i][EO_index,:,:]
# # Save to list
# STC_eye_data.append([EC_epoch_data, EO_epoch_data])
# # Make each epoch a TimeSeries object
# # Input for TimeSeries is: (ch, time)
# eye_status = list(final_epochs[0].event_id.keys())
# n_eye_status = len(eye_status)
# sfreq = final_epochs[0].info["sfreq"]
# Timeseries_data = []
# for i in range(n_subjects):
# temp_list1 = []
# for e in range(n_eye_status):
# temp_list2 = []
# n_epochs = STC_eye_data[i][e].shape[0]
# for ep in range(n_epochs):
# # Convert to TimeSeries
# time_series = nts.TimeSeries(STC_eye_data[i][e][ep,:,:], sampling_rate=sfreq)
# # Save the object
# temp_list2.append(time_series)
# # Save the timeseries across eye status