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README.md
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README.md
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# Reproduction: Mwata-Velu et al. (2023)
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**Paper**: "EEG-BCI Features Discrimination between Executed and Imagined Movements
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Based on FastICA, Hjorth Parameters, and SVM"
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**Journal**: Mathematics 2023, 11, 4409
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**DOI**: https://doi.org/10.3390/math11214409
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## Overview
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This repository contains an attempted reproduction of the above paper as part of a
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thesis on reproducibility challenges in EEG-based BCI research. The reproduction was
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**partially completed** — the core pipeline is implemented but several ambiguities in the
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paper prevented a definitive reproduction.
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## Repository Structure
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```
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config.py — Constants, channel lists, run mappings, parameters
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data_loading.py — CSV data loading, MNE Raw creation, annotations
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pipeline.py — Filtering, FastICA, Hjorth features, SVM classification
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reproduction_notebook.ipynb — Main analysis notebook (Method 2: cross-subject)
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requirements.txt — Python dependencies
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```
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## Data
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This code expects the PhysioNet EEG Motor Movement/Imagery Dataset in the curated
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CSV format provided by:
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Z. Shuqfa, A. Lakas, and A. N. Belkacem, “Increasing accessibility to a large brain–
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computer interface dataset: Curation of physionet EEG motor movement/imagery dataset
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for decoding and classification,” Data in Brief, vol. 54, p. 110181, Jun. 2024,
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doi: 10.1016/j.dib.2024.110181.
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Files are named:
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- `eegmmidb/SUB_001_SIG_01.csv` — Signal data (n_samples × 64 channels)
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- `eegmmidb/SUB_001_ANN_01.csv` — Annotations (label, duration, start/end rows)
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The curated dataset excludes the 6 problematic subjects (S088, S089, S092, S100,
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S104, S106) noted in the paper. Run numbering is offset by 2 from PhysioNet's
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original (our Run 01 = PhysioNet R03).
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## Usage
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1. Install dependencies: `pip install -r requirements.txt`
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2. Place curated CSV data in `eegmmidb/` directory
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3. Edit `config.py` to set `ICA_STRATEGY` ('per_run', 'per_subject', or 'global')
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4. Run `reproduction_notebook.ipynb`
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## Key Implementation Decisions
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| Decision | Paper says | We do | Rationale |
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|----------|-----------|-------|----------|
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| Pipeline order | Figure 1: filter→ICA; Algorithm 1: ICA with internal sub-band eval | ICA then sub-band eval | Energy criterion is meaningless on pre-filtered data |
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| ICA algorithm | Gram-Schmidt (Algorithm 1, Step 3) | `algorithm='deflation'` | Deflation uses Gram-Schmidt |
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| Energy criterion | ∀χ ∈ {α, β, **γ**} | ∀χ ∈ {**θ**, α, β} | γ never defined; likely typo for θ |
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| ICA scope | Not specified | Configurable | Reproducibility variable |
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| Classification Method | Methods 1 and 2 | Method 2 only (cross-subject) | Method 1 split is contradictory |
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## Paper's Reported Results (Method 2, Set 3)
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| Metric | Paper |
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|--------|-------|
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| Overall accuracy | 68.8 ± 0.71% |
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| ME recall | 68.17% |
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| MI recall | 68.41% |
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144
config.py
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config.py
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"""
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Configuration for reproducing Mwata-Velu et al. (2023)
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"EEG-BCI Features Discrimination between Executed and Imagined Movements
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Based on FastICA, Hjorth Parameters, and SVM"
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Mathematics 2023, 11, 4409. DOI: 10.3390/math11214409
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Dataset: PhysioNet EEG Motor Movement/Imagery Dataset (curated CSV format)
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"""
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from pathlib import Path
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# =============================================================================
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# Paths
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# =============================================================================
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DATA_DIR = Path("..\eegmmidb")
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# =============================================================================
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# Dataset parameters
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# =============================================================================
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SAMPLING_RATE = 160 # Hz
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N_CHANNELS = 64
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# Full 64-channel names (Sharbrough system, PhysioNet ordering)
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CHANNEL_NAMES = [
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'FC5', 'FC3', 'FC1', 'FCz', 'FC2', 'FC4', 'FC6',
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'C5', 'C3', 'C1', 'Cz', 'C2', 'C4', 'C6',
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'CP5', 'CP3', 'CP1', 'CPz', 'CP2', 'CP4', 'CP6',
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'Fp1', 'Fpz', 'Fp2',
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'AF7', 'AF3', 'AFz', 'AF4', 'AF8',
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'F7', 'F5', 'F3', 'F1', 'Fz', 'F2', 'F4', 'F6', 'F8',
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'FT7', 'FT8',
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'T7', 'T8', 'T9', 'T10',
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'TP7', 'TP8',
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'P7', 'P5', 'P3', 'P1', 'Pz', 'P2', 'P4', 'P6', 'P8',
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'PO7', 'PO3', 'POz', 'PO4', 'PO8',
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'O1', 'Oz', 'O2',
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'Iz',
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]
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# =============================================================================
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# Channel selections (Section 3.2)
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# =============================================================================
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# 19 channels from the 10-20 system used for ICA decomposition (Section 3.2)
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ICA_CHANNELS = [
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'Fp1', 'Fp2', 'F7', 'F3', 'Fz', 'F4', 'F8',
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'T7', 'C3', 'Cz', 'C4', 'T8',
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'P7', 'P3', 'Pz', 'P4', 'P8', 'O1', 'O2',
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]
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# 9 "Selected_channels" for ICA energy concentration criterion (Algorithm 1, Step 7)
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# These are the sensorimotor + frontal + parietal channels the paper evaluates
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# energy concentration against.
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SELECTED_CHANNELS = ['C3', 'Cz', 'C4', 'F3', 'Fz', 'F4', 'P3', 'Pz', 'P4']
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# Channels used for Hjorth feature extraction (Section 3.5, Table 5)
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# The paper's best results (Set 3) use C3, Cz, C4.
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TARGET_CHANNELS = ['C3', 'Cz', 'C4']
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# =============================================================================
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# Task / run definitions
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# =============================================================================
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# NOTE ON NUMBERING: The curated CSV dataset uses a different run numbering
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# scheme than the original PhysioNet EDF files. The mapping is:
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#
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# Curated CSV PhysioNet EDF Task
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# ----------- ------------- ----
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# Run 01 R03 Execute open/close left or right fist
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# Run 02 R04 Imagine open/close left or right fist
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# Run 03 R05 Execute open/close both fists or both feet
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# Run 04 R06 Imagine open/close both fists or both feet
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# Run 05 R07 Execute open/close left or right fist
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# Run 06 R08 Imagine open/close left or right fist
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# Run 07 R09 Execute open/close both fists or both feet
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# Run 08 R10 Imagine open/close both fists or both feet
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# Run 09 R11 Execute open/close left or right fist
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# Run 10 R12 Imagine open/close left or right fist
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# Run 11 R13 Execute open/close both fists or both feet
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# Run 12 R14 Imagine open/close both fists or both feet
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#
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# The paper's Section 4 states twice that results correspond to R03, R04, R07,
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# R08, R11, R12 (left/right fist only). This agrees with another statement
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# that says they only use 6 of the 14 runs per subject. However, the sample
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# counts (8652 total) require including all 12 task runs. Additionally, the
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# paper also says "samples of the first 10 runs constituted the training set;
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# those of the 11th and 12th, and 13th and 14th runs were used as the testing
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# and validation sets, respectively". These statements contradict each other.
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# We use the 6 runs that are listed twice: R03, R04, R07, R08, R11, R12.
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EXECUTION_RUNS = [1, 5, 9] # R03, R07, R11
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IMAGERY_RUNS = [2, 6, 10] # R04, R08, R12
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TARGET_RUNS = EXECUTION_RUNS + IMAGERY_RUNS
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# Annotation labels that correspond to T1/T2 events (active task periods).
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# T0 (rest) is excluded. These codes come from the curated CSV annotation files.
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ACTIVE_EVENT_LABELS = [2, 3, 5, 6, 8, 9, 11, 12]
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# =============================================================================
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# Sub-band definitions (Section 3.3)
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# =============================================================================
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SUB_BANDS = [
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('theta', 4.0, 8.0),
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('alpha', 8.0, 13.0),
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('beta', 13.0, 30.0),
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]
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# =============================================================================
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# ICA parameters (Section 3.4, Algorithm 1)
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# =============================================================================
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ICA_N_COMPONENTS = 19
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ICA_ENERGY_THRESHOLD = 0.35
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ICA_MAX_ITER = 500
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ICA_TOL = 1e-4
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# =============================================================================
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# SVM parameters (Section 3.6, Figure 6)
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# =============================================================================
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SVM_C = 2 ** 13 # 8192
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SVM_GAMMA = 2 ** 1 # 2
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SVM_KERNEL = 'rbf'
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# =============================================================================
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# Evaluation
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# =============================================================================
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N_RUNS = 5 # Paper: "results were averaged by running the model five times"
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RANDOM_SEEDS = [42, 123, 456, 789, 1024]
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# =============================================================================
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# ICA strategy (not specified in paper — this is a reproducibility variable)
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# =============================================================================
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# Options:
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# 'per_run' — Fit ICA independently on each ~2-minute run
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# 'per_subject' — Fit ICA once on all runs concatenated per subject
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# 'global' — Fit ICA once on all training subjects concatenated
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ICA_STRATEGY = 'per_subject'
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# =============================================================================
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# Method 2: Cross-Subject Split (Table 4)
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# =============================================================================
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# Note: The curated dataset already excludes the 6 problematic subjects
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# (S088, S089, S092, S100, S104, S106), so we use consecutive IDs.
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TRAIN_SUBJECTS = list(range(1, 84)) # Subjects 1-83
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TEST_SUBJECTS = list(range(84, 94)) # Subjects 84-93
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VAL_SUBJECTS = list(range(94, 104)) # Subjects 94-103
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data_loading.py
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data_loading.py
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"""
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Data loading utilities for the curated PhysioNet EEG Motor Movement/Imagery
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dataset (CSV format).
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"""
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import numpy as np
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import pandas as pd
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import mne
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from config import DATA_DIR, N_CHANNELS, CHANNEL_NAMES, SAMPLING_RATE
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def load_signal_file(subject_num, run_num, data_dir=DATA_DIR):
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"""
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Load EEG signal from CSV file.
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Returns
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-------
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np.ndarray of shape (n_samples, N_CHANNELS)
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"""
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filename = f"SUB_{subject_num:03d}_SIG_{run_num:02d}.csv"
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filepath = data_dir / filename
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if not filepath.exists():
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raise FileNotFoundError(f"File not found: {filepath}")
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data = pd.read_csv(filepath, header=None).values
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if data.shape[1] != N_CHANNELS:
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raise ValueError(f"Expected {N_CHANNELS} channels, got {data.shape[1]}")
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return data
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def load_annotation_file(subject_num, run_num, data_dir=DATA_DIR):
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"""
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Load annotations from CSV file.
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Returns
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-------
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pd.DataFrame with columns ['label', 'duration_sec', 'n_rows', 'start_row', 'end_row']
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"""
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filename = f"SUB_{subject_num:03d}_ANN_{run_num:02d}.csv"
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filepath = data_dir / filename
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if not filepath.exists():
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raise FileNotFoundError(f"File not found: {filepath}")
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annotations = pd.read_csv(filepath)
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expected_cols = ['label', 'duration_sec', 'n_rows', 'start_row', 'end_row']
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if list(annotations.columns) != expected_cols:
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if len(annotations.columns) == 5:
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annotations.columns = expected_cols
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else:
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raise ValueError(
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f"Expected 5 columns {expected_cols}, got {len(annotations.columns)}: "
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f"{list(annotations.columns)}"
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)
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return annotations
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def create_mne_raw(signal_data, sfreq=SAMPLING_RATE):
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"""
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Create MNE Raw object from signal data.
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Parameters
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----------
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signal_data : np.ndarray of shape (n_samples, N_CHANNELS)
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Returns
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-------
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mne.io.RawArray
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"""
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# Transpose to (channels, samples) and convert µV → V
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data = signal_data.T * 1e-6
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info = mne.create_info(
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ch_names=CHANNEL_NAMES,
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sfreq=sfreq,
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ch_types='eeg',
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)
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raw = mne.io.RawArray(data, info, verbose=False)
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# Set standard 10-20 montage
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montage = mne.channels.make_standard_montage('standard_1005')
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# Only set channels that exist in the montage
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valid_chs = [ch for ch in raw.ch_names if ch in montage.ch_names]
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raw = raw.pick(valid_chs)
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raw.set_montage(montage, on_missing='ignore')
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return raw
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def add_annotations_to_raw(raw, annotations_df):
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"""
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Add event annotations to MNE Raw object.
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Parameters
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----------
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raw : mne.io.Raw
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annotations_df : pd.DataFrame with start_row, duration_sec, label columns
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Returns
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-------
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mne.io.Raw with annotations added
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"""
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sfreq = raw.info['sfreq']
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onsets = annotations_df['start_row'].values / sfreq
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durations = annotations_df['duration_sec'].values
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descriptions = [str(int(label)) for label in annotations_df['label'].values]
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annot = mne.Annotations(onset=onsets, duration=durations,
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description=descriptions)
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raw.set_annotations(annot)
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return raw
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910
pipeline.py
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pipeline.py
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"""
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Core signal processing pipeline for reproducing Mwata-Velu et al. (2023).
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Contains:
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- Chebyshev Type II sub-band filtering (Section 3.3)
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- FastICA denoising with energy concentration criterion (Section 3.4, Algorithm 1)
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- Hjorth parameter feature extraction (Section 3.5)
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- SVM classification with 5-run averaging (Section 3.6)
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PIPELINE ORDER (Algorithm 1 interpretation):
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1. ICA on broadband 19-channel data
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- Step 6 internally filters each back-projected IC into θ/α/β sub-bands
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to evaluate energy concentration in selected channels
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- Step 7 keeps only ICs meeting the threshold in ANY sub-band (OR logic).
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The paper specifies ALL (AND logic), but this causes zero components
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to pass for many subjects. OR logic is used as a documented deviation.
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- Step 8 reconstructs cleaned broadband signal from kept ICs
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2. Filter the *cleaned* broadband signal into θ/α/β for Hjorth Activity features
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3. Compute Hjorth Mobility/Complexity on the *cleaned* unfiltered signal
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This resolves the paper's contradiction between Figure 1 and Algorithm 1. The
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Algorithm 1 reading is preferred because the energy concentration criterion is
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meaningless on pre-filtered data (e.g., filtering theta-band data into alpha
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yields ~zero).
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"""
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import numpy as np
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from scipy.signal import cheby2, filtfilt
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import mne
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from mne.preprocessing import ICA
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from sklearn.svm import SVC
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from sklearn.preprocessing import MinMaxScaler
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from sklearn.metrics import accuracy_score, confusion_matrix, classification_report
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from config import (
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ICA_CHANNELS, SELECTED_CHANNELS, SUB_BANDS, TARGET_RUNS,
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ICA_N_COMPONENTS, ICA_ENERGY_THRESHOLD, ICA_MAX_ITER, ICA_TOL,
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TARGET_CHANNELS, EXECUTION_RUNS, IMAGERY_RUNS, ACTIVE_EVENT_LABELS,
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SVM_C, SVM_GAMMA, SVM_KERNEL, N_RUNS, RANDOM_SEEDS,
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)
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from data_loading import (
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load_signal_file, load_annotation_file, create_mne_raw, add_annotations_to_raw,
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)
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# =============================================================================
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# Sub-band filtering (Section 3.3)
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# =============================================================================
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def design_chebyshev_filter(lowcut, highcut, fs, order=5, rs=34):
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"""
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Design Chebyshev Type II bandpass filter.
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Paper specifies:
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- 5th-order Chebyshev Type II
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- Stop-band attenuation of -34 dB
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- Transition bands reaching 80% of the gain
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"""
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nyq = 0.5 * fs
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low = lowcut / nyq
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high = highcut / nyq
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b, a = cheby2(order, rs, [low, high], btype='band')
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return b, a
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def apply_bandpass_filter(raw, lowcut, highcut, picks=None):
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"""
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Apply Chebyshev Type II bandpass filter.
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Parameters
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----------
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raw : mne.io.Raw
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lowcut, highcut : float
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picks : list of str, optional
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Channel names to filter. If None, filters all channels.
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When specified, returns a Raw containing only those channels.
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Returns a new Raw object with filtered data.
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"""
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if picks is not None:
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raw_sub = raw.copy().pick(picks)
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else:
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raw_sub = raw.copy()
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b, a = design_chebyshev_filter(lowcut, highcut, raw_sub.info['sfreq'])
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data = raw_sub.get_data()
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filtered_data = filtfilt(b, a, data, axis=1)
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raw_filtered = mne.io.RawArray(filtered_data, raw_sub.info, verbose=False)
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raw_filtered.set_annotations(raw.annotations)
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return raw_filtered
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def _cheby2_bandpass(data, sfreq, low, high, order=5, rs=34.0):
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"""
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Apply Chebyshev Type II bandpass filter to a numpy array.
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Used internally by the ICA energy concentration criterion (Step 6-7).
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Parameters
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----------
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data : ndarray, shape (n_signals, n_samples)
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sfreq : float
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low, high : float, pass-band edges in Hz
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Returns
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-------
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filtered : ndarray, same shape as data
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"""
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b, a = design_chebyshev_filter(low, high, sfreq, order=order, rs=rs)
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return filtfilt(b, a, data, axis=-1)
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||||
|
||||
|
||||
# =============================================================================
|
||||
# FastICA denoising (Section 3.4, Algorithm 1)
|
||||
# =============================================================================
|
||||
|
||||
def apply_fastica_denoising(raw, n_components=ICA_N_COMPONENTS,
|
||||
energy_threshold=ICA_ENERGY_THRESHOLD,
|
||||
verbose=True):
|
||||
"""
|
||||
Denoise EEG with FastICA following Algorithm 1 of Mwata-Velu et al. (2023).
|
||||
|
||||
This function operates on BROADBAND data. Sub-band filtering is used
|
||||
internally only for the energy concentration criterion (Steps 6-7).
|
||||
|
||||
Steps mapped to the paper
|
||||
-------------------------
|
||||
Steps 1-5: FastICA decomposition of 19 channels into n_components ICs.
|
||||
- Step 1: Random weight vector initialization
|
||||
- Step 2: Fixed-point update with log-cosh non-linearity (Eq. 3-4)
|
||||
- Step 3: Gram-Schmidt orthogonalization (deflation approach)
|
||||
- Step 4: Weight vector normalization
|
||||
- Step 5: Convergence check; repeat 2-4 if not converged
|
||||
|
||||
NOTE: We use algorithm='deflation' to match the paper's explicit
|
||||
description of Gram-Schmidt orthogonalization. sklearn's default
|
||||
('parallel') uses symmetric decorrelation instead, which is a
|
||||
different algorithm. See Hyvärinen & Oja (1997, 2000).
|
||||
|
||||
Step 6: For every IC k, back-project to 19 channels, filter into each
|
||||
sub-band, and compute per-channel variance.
|
||||
|
||||
Step 7: Retain IC k if, for ANY sub-band, the ratio
|
||||
sum(Selected) / sum(All) >= threshold (paper: 0.35).
|
||||
|
||||
NOTE: The paper specifies AND logic (all sub-bands must pass),
|
||||
but this is too strict — many subjects yield zero kept components.
|
||||
We use OR logic (any sub-band passing suffices) as a documented
|
||||
reproducibility deviation.
|
||||
|
||||
NOTE: The paper writes {γ, α, β}" with gamma instead of theta.
|
||||
The gamma band is never defined in the paper. We interpret this as a
|
||||
typo and use θ/α/β as defined in Section 3.3.
|
||||
|
||||
Step 8: Reconstruct û = A_p @ S_p using only kept components.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
raw : mne.io.Raw
|
||||
Must contain (at least) the 19 ICA_CHANNELS.
|
||||
Should be BROADBAND (unfiltered) data.
|
||||
n_components : int
|
||||
Number of ICs to extract. Paper uses 19.
|
||||
energy_threshold : float
|
||||
Per-sub-band concentration ratio threshold. Paper: 0.35.
|
||||
verbose : bool
|
||||
Print progress information.
|
||||
|
||||
Returns
|
||||
-------
|
||||
raw_clean : mne.io.Raw
|
||||
Copy of raw with denoised ICA channels (still broadband).
|
||||
ica : mne.preprocessing.ICA
|
||||
Fitted ICA object.
|
||||
kept_components : list of int
|
||||
Indices of ICs that passed the Step 7 criterion.
|
||||
"""
|
||||
sfreq = raw.info['sfreq']
|
||||
if verbose:
|
||||
print(f" [FastICA] {n_components} components, "
|
||||
f"threshold={energy_threshold}, deflation mode")
|
||||
|
||||
# ------------------------------------------------------------------
|
||||
# Steps 1-5: FastICA decomposition on broadband data
|
||||
# ------------------------------------------------------------------
|
||||
raw_ica = raw.copy().pick(ICA_CHANNELS)
|
||||
|
||||
ica = ICA(
|
||||
n_components=n_components,
|
||||
method='fastica',
|
||||
fit_params={
|
||||
'max_iter': ICA_MAX_ITER,
|
||||
'tol': ICA_TOL,
|
||||
'algorithm': 'deflation', # Paper's Algorithm 1, Step 3
|
||||
},
|
||||
random_state=42,
|
||||
)
|
||||
ica.fit(raw_ica)
|
||||
|
||||
# Mixing matrix A and IC time-series S
|
||||
mixing = ica.mixing_matrix_
|
||||
unmixing = ica.unmixing_matrix_
|
||||
raw_data = raw_ica.get_data()
|
||||
icasigs = unmixing @ raw_data
|
||||
|
||||
# Channel index maps
|
||||
all_ch_names = list(raw_ica.ch_names)
|
||||
sel_idx = [all_ch_names.index(ch) for ch in SELECTED_CHANNELS]
|
||||
|
||||
# ------------------------------------------------------------------
|
||||
# Step 6: Evaluate each IC by sub-band (internal filtering)
|
||||
#
|
||||
# For each IC k:
|
||||
# 1. Back-project to 19 channels: signal[c, t] = mixing[c, k] * IC_k[t]
|
||||
# 2. Filter the 19-channel signal into each sub-band
|
||||
# 3. Compute variance per channel
|
||||
# ------------------------------------------------------------------
|
||||
ic_channel_var = {name: [] for name, _, _ in SUB_BANDS}
|
||||
|
||||
for k in range(n_components):
|
||||
signal_19ch = mixing[:, k, np.newaxis] * icasigs[k, :] # (19, T)
|
||||
|
||||
for name, low, high in SUB_BANDS:
|
||||
filtered = _cheby2_bandpass(signal_19ch, sfreq, low, high)
|
||||
var_per_channel = np.var(filtered, axis=1, ddof=1)
|
||||
ic_channel_var[name].append(var_per_channel)
|
||||
|
||||
for name in ic_channel_var:
|
||||
ic_channel_var[name] = np.array(ic_channel_var[name])
|
||||
|
||||
# ------------------------------------------------------------------
|
||||
# Step 7: Energy concentration criterion
|
||||
#
|
||||
# Paper states: ∀χ ∈ {θ, α, β} (AND logic).
|
||||
# However, AND across all three bands is extremely strict and causes
|
||||
# zero components to pass for many subjects. We use OR logic instead:
|
||||
# keep IC k if it passes the threshold in ANY sub-band. This is more
|
||||
# defensible — a component concentrated in motor cortex in alpha is
|
||||
# still a neural signal worth keeping even if its theta energy is
|
||||
# diffuse. Documented as a reproducibility deviation.
|
||||
# ------------------------------------------------------------------
|
||||
kept_components = []
|
||||
|
||||
if verbose:
|
||||
print(f" {'IC':>4} | {'theta':>7} | {'alpha':>7} | {'beta':>7} | {'kept?':>5}")
|
||||
print(f" {'-'*46}")
|
||||
|
||||
for k in range(n_components):
|
||||
ratios = {}
|
||||
keep = False # OR logic: start False, flip to True if ANY passes
|
||||
# keep = True # AND logic: start True, flip to False if ANY fails
|
||||
|
||||
for name, _, _ in SUB_BANDS:
|
||||
var_all = ic_channel_var[name][k]
|
||||
num = var_all[sel_idx].sum()
|
||||
den = var_all.sum()
|
||||
ratio = num / den if den > 0 else 0.0
|
||||
ratios[name] = ratio
|
||||
if ratio >= energy_threshold:
|
||||
keep = True # passes in at least one sub-band
|
||||
# if ratio < energy_threshold:
|
||||
# keep = False # fails in at least one sub-band
|
||||
|
||||
if verbose:
|
||||
status = "YES" if keep else "no"
|
||||
print(f" {k:>4} | {ratios['theta']:>7.3f} | "
|
||||
f"{ratios['alpha']:>7.3f} | {ratios['beta']:>7.3f} | {status:>5}")
|
||||
|
||||
if keep:
|
||||
kept_components.append(k)
|
||||
|
||||
if verbose:
|
||||
print(f" [FastICA] Kept {len(kept_components)}/{n_components} components")
|
||||
|
||||
# ------------------------------------------------------------------
|
||||
# Step 8: Reconstruct û = A_p @ S_p (broadband cleaned signal)
|
||||
# ------------------------------------------------------------------
|
||||
if len(kept_components) == 0:
|
||||
if verbose:
|
||||
print(" [FastICA] WARNING: no components passed threshold "
|
||||
"even with OR logic. Returning original data unchanged.")
|
||||
return raw.copy(), ica, kept_components
|
||||
|
||||
A_p = mixing[:, kept_components]
|
||||
S_p = icasigs[kept_components, :]
|
||||
reconstructed = A_p @ S_p
|
||||
|
||||
raw_clean = mne.io.RawArray(reconstructed, raw_ica.info, verbose=False)
|
||||
raw_clean.set_annotations(raw.annotations)
|
||||
return raw_clean, ica, kept_components
|
||||
|
||||
|
||||
# =============================================================================
|
||||
# Hjorth parameter extraction (Section 3.5)
|
||||
# =============================================================================
|
||||
|
||||
def compute_hjorth_parameters(signal_array):
|
||||
"""
|
||||
Compute Hjorth parameters: Activity, Mobility, Complexity.
|
||||
|
||||
Activity: Variance of the signal (Eq. 5)
|
||||
Mobility: sqrt(Var(d/dt signal) / Var(signal)) (Eq. 6)
|
||||
Complexity: Mobility(d/dt signal) / Mobility(signal) (Eq. 7)
|
||||
|
||||
The derivative d/dt u(i) is approximated as u(i) - u(i-1) per the paper.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
signal_array : np.ndarray, 1D
|
||||
|
||||
Returns
|
||||
-------
|
||||
activity, mobility, complexity : float
|
||||
"""
|
||||
activity = np.var(signal_array)
|
||||
|
||||
d1 = np.diff(signal_array)
|
||||
var_d1 = np.var(d1)
|
||||
|
||||
if activity > 0:
|
||||
mobility = np.sqrt(var_d1 / activity)
|
||||
else:
|
||||
mobility = 0.0
|
||||
|
||||
d2 = np.diff(d1)
|
||||
var_d2 = np.var(d2)
|
||||
|
||||
if var_d1 > 0 and mobility > 0:
|
||||
mobility_d1 = np.sqrt(var_d2 / var_d1)
|
||||
complexity = mobility_d1 / mobility
|
||||
else:
|
||||
complexity = 0.0
|
||||
|
||||
return activity, mobility, complexity
|
||||
|
||||
|
||||
def extract_epoch_features(data_raw, data_theta, data_alpha, data_beta,
|
||||
channels=TARGET_CHANNELS):
|
||||
"""
|
||||
Extract Hjorth features for one epoch across all target channels.
|
||||
|
||||
Feature set matches Table 5, Set 3: Aθ, Aα, Aβ, Mraw, Craw per channel.
|
||||
Total features = len(channels) * 5.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
data_raw, data_theta, data_alpha, data_beta : np.ndarray
|
||||
Shape (n_channels, n_samples) epoch data for each band.
|
||||
|
||||
Returns
|
||||
-------
|
||||
features : np.ndarray of shape (n_channels * 5,)
|
||||
"""
|
||||
features = []
|
||||
for i in range(len(channels)):
|
||||
a_theta, _, _ = compute_hjorth_parameters(data_theta[i])
|
||||
a_alpha, _, _ = compute_hjorth_parameters(data_alpha[i])
|
||||
a_beta, _, _ = compute_hjorth_parameters(data_beta[i])
|
||||
_, m_raw, c_raw = compute_hjorth_parameters(data_raw[i])
|
||||
features.extend([a_theta, a_alpha, a_beta, m_raw, c_raw])
|
||||
return np.array(features)
|
||||
|
||||
|
||||
# =============================================================================
|
||||
# Subject processing (orchestration)
|
||||
#
|
||||
# In all strategies below, the pipeline is:
|
||||
# 1. ICA on broadband data (1 fit, not 4)
|
||||
# 2. Filter the CLEANED broadband signal into θ/α/β for Activity features
|
||||
# 3. Compute Mobility/Complexity on the CLEANED unfiltered signal
|
||||
# =============================================================================
|
||||
|
||||
def process_subject_per_run(subject_num, target_runs=None, apply_ica=True,
|
||||
verbose=True):
|
||||
"""
|
||||
Process one subject with ICA fitted independently per run.
|
||||
|
||||
This gives ICA the least amount of data to work with (~19,200 samples for
|
||||
a 2-minute run on 19 channels).
|
||||
|
||||
Returns
|
||||
-------
|
||||
all_features : list of np.ndarray, one per run
|
||||
all_labels : list of np.ndarray, one per run
|
||||
run_numbers : list of int
|
||||
total_kept : int (total across all ICA fits)
|
||||
"""
|
||||
if target_runs is None:
|
||||
target_runs = TARGET_RUNS
|
||||
|
||||
all_features = []
|
||||
all_labels = []
|
||||
run_numbers = []
|
||||
total_kept = 0
|
||||
n_ica_fits = 0
|
||||
|
||||
for run_num in target_runs:
|
||||
try:
|
||||
signal_data = load_signal_file(subject_num, run_num)
|
||||
annotations = load_annotation_file(subject_num, run_num)
|
||||
except Exception as e:
|
||||
if verbose:
|
||||
print(f" Could not load S{subject_num:03d} R{run_num:02d}: {e}")
|
||||
continue
|
||||
|
||||
raw = create_mne_raw(signal_data)
|
||||
raw = add_annotations_to_raw(raw, annotations)
|
||||
|
||||
# ICA on broadband data (1 fit per run; sub-band eval is internal)
|
||||
if apply_ica:
|
||||
raw_clean, _, kept = apply_fastica_denoising(raw, verbose=verbose)
|
||||
total_kept += len(kept)
|
||||
n_ica_fits += 1
|
||||
else:
|
||||
raw_clean = raw
|
||||
|
||||
# Filter the CLEANED signal into sub-bands for Activity features
|
||||
# Only filter the channels we actually need for feature extraction
|
||||
raw_theta = apply_bandpass_filter(raw_clean, 4, 8, picks=TARGET_CHANNELS)
|
||||
raw_alpha = apply_bandpass_filter(raw_clean, 8, 13, picks=TARGET_CHANNELS)
|
||||
raw_beta = apply_bandpass_filter(raw_clean, 13, 30, picks=TARGET_CHANNELS)
|
||||
|
||||
# Determine task type from run number
|
||||
if run_num in EXECUTION_RUNS:
|
||||
task_type = 'ME'
|
||||
elif run_num in IMAGERY_RUNS:
|
||||
task_type = 'MI'
|
||||
else:
|
||||
continue
|
||||
|
||||
# Extract features from active events
|
||||
features_list, labels_list = _extract_run_features(
|
||||
raw_clean, raw_theta, raw_alpha, raw_beta,
|
||||
annotations, task_type
|
||||
)
|
||||
|
||||
if len(features_list) > 0:
|
||||
all_features.append(np.array(features_list))
|
||||
all_labels.append(np.array(labels_list))
|
||||
run_numbers.append(run_num)
|
||||
|
||||
return all_features, all_labels, run_numbers, total_kept
|
||||
|
||||
|
||||
def process_subject_per_subject(subject_num, target_runs=None, apply_ica=True,
|
||||
verbose=True):
|
||||
"""
|
||||
Process one subject with ICA fitted once on all runs concatenated.
|
||||
|
||||
This gives ICA more data for better decomposition (~115,200 samples
|
||||
for 12 runs).
|
||||
|
||||
Returns
|
||||
-------
|
||||
all_features : list of np.ndarray, one per run
|
||||
all_labels : list of np.ndarray, one per run
|
||||
run_numbers : list of int
|
||||
n_kept_components : int
|
||||
"""
|
||||
if target_runs is None:
|
||||
target_runs = TARGET_RUNS
|
||||
|
||||
# Step 1: Load and concatenate all runs
|
||||
raw_runs = []
|
||||
annotations_runs = []
|
||||
run_lengths = []
|
||||
|
||||
for run_num in target_runs:
|
||||
try:
|
||||
signal_data = load_signal_file(subject_num, run_num)
|
||||
annotations = load_annotation_file(subject_num, run_num)
|
||||
raw = create_mne_raw(signal_data)
|
||||
raw = add_annotations_to_raw(raw, annotations)
|
||||
raw_runs.append(raw)
|
||||
annotations_runs.append(annotations)
|
||||
run_lengths.append(raw.n_times)
|
||||
except Exception as e:
|
||||
if verbose:
|
||||
print(f" Could not load S{subject_num:03d} R{run_num:02d}: {e}")
|
||||
continue
|
||||
|
||||
if len(raw_runs) == 0:
|
||||
return [], [], [], 0
|
||||
|
||||
raw_concat = mne.concatenate_raws(raw_runs, preload=True)
|
||||
if verbose:
|
||||
duration = raw_concat.n_times / raw_concat.info['sfreq']
|
||||
print(f" S{subject_num:03d}: {len(raw_runs)} runs, {duration:.0f}s")
|
||||
|
||||
# Step 2: ICA once on broadband concatenated data
|
||||
n_kept = 0
|
||||
if apply_ica:
|
||||
raw_clean, _, kept = apply_fastica_denoising(raw_concat, verbose=verbose)
|
||||
n_kept = len(kept)
|
||||
else:
|
||||
raw_clean = raw_concat
|
||||
|
||||
# Step 3: Filter the CLEANED signal into sub-bands for Activity features
|
||||
# Only filter the channels we actually need for feature extraction
|
||||
raw_theta = apply_bandpass_filter(raw_clean, 4, 8, picks=TARGET_CHANNELS)
|
||||
raw_alpha = apply_bandpass_filter(raw_clean, 8, 13, picks=TARGET_CHANNELS)
|
||||
raw_beta = apply_bandpass_filter(raw_clean, 13, 30, picks=TARGET_CHANNELS)
|
||||
|
||||
# Step 4: Extract features per run using global sample offsets
|
||||
all_raw_data = raw_clean.get_data()
|
||||
all_theta_data = raw_theta.get_data()
|
||||
all_alpha_data = raw_alpha.get_data()
|
||||
all_beta_data = raw_beta.get_data()
|
||||
|
||||
ch_idx_clean = [raw_clean.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_theta = [raw_theta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_alpha = [raw_alpha.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_beta = [raw_beta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
|
||||
all_features = []
|
||||
all_labels = []
|
||||
run_numbers = []
|
||||
sample_offset = 0
|
||||
|
||||
for run_idx, run_num in enumerate(target_runs):
|
||||
if run_idx >= len(raw_runs):
|
||||
continue
|
||||
|
||||
annotations = annotations_runs[run_idx]
|
||||
run_length = run_lengths[run_idx]
|
||||
|
||||
if run_num in EXECUTION_RUNS:
|
||||
task_type = 'ME'
|
||||
elif run_num in IMAGERY_RUNS:
|
||||
task_type = 'MI'
|
||||
else:
|
||||
sample_offset += run_length
|
||||
continue
|
||||
|
||||
features_list, labels_list = _extract_run_features_from_arrays(
|
||||
all_raw_data, all_theta_data, all_alpha_data, all_beta_data,
|
||||
ch_idx_clean, ch_idx_theta, ch_idx_alpha, ch_idx_beta,
|
||||
annotations, task_type, sample_offset, all_raw_data.shape[1]
|
||||
)
|
||||
|
||||
if len(features_list) > 0:
|
||||
all_features.append(np.array(features_list))
|
||||
all_labels.append(np.array(labels_list))
|
||||
run_numbers.append(run_num)
|
||||
|
||||
sample_offset += run_length
|
||||
|
||||
return all_features, all_labels, run_numbers, n_kept
|
||||
|
||||
|
||||
def process_subject_global(subject_num, global_ica_results,
|
||||
target_runs=None, verbose=True):
|
||||
"""
|
||||
Process one subject using a pre-fitted global ICA.
|
||||
|
||||
The global ICA is fitted once on all training subjects' broadband data.
|
||||
Each subject's data is then projected through the same unmixing matrix.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
subject_num : int
|
||||
global_ica_results : dict
|
||||
Keys: 'mixing', 'unmixing', 'kept_components'
|
||||
From fit_global_ica().
|
||||
target_runs : list of int, optional
|
||||
verbose : bool
|
||||
|
||||
Returns
|
||||
-------
|
||||
all_features, all_labels, run_numbers, n_kept
|
||||
"""
|
||||
if target_runs is None:
|
||||
target_runs = TARGET_RUNS
|
||||
|
||||
# Load and concatenate
|
||||
raw_runs = []
|
||||
annotations_runs = []
|
||||
run_lengths = []
|
||||
|
||||
for run_num in target_runs:
|
||||
try:
|
||||
signal_data = load_signal_file(subject_num, run_num)
|
||||
annotations = load_annotation_file(subject_num, run_num)
|
||||
raw = create_mne_raw(signal_data)
|
||||
raw = add_annotations_to_raw(raw, annotations)
|
||||
raw_runs.append(raw)
|
||||
annotations_runs.append(annotations)
|
||||
run_lengths.append(raw.n_times)
|
||||
except Exception:
|
||||
continue
|
||||
|
||||
if len(raw_runs) == 0:
|
||||
return [], [], [], 0
|
||||
|
||||
raw_concat = mne.concatenate_raws(raw_runs, preload=True)
|
||||
|
||||
# Apply pre-fitted global ICA on broadband data
|
||||
ica_tuple = (global_ica_results['mixing'],
|
||||
global_ica_results['unmixing'],
|
||||
global_ica_results['kept_components'])
|
||||
raw_clean = _apply_precomputed_ica(raw_concat, ica_tuple)
|
||||
n_kept = len(global_ica_results['kept_components'])
|
||||
|
||||
# Filter the CLEANED signal into sub-bands for Activity features
|
||||
# Only filter the channels we actually need for feature extraction
|
||||
raw_theta = apply_bandpass_filter(raw_clean, 4, 8, picks=TARGET_CHANNELS)
|
||||
raw_alpha = apply_bandpass_filter(raw_clean, 8, 13, picks=TARGET_CHANNELS)
|
||||
raw_beta = apply_bandpass_filter(raw_clean, 13, 30, picks=TARGET_CHANNELS)
|
||||
|
||||
# Extract features per run
|
||||
all_raw_data = raw_clean.get_data()
|
||||
all_theta_data = raw_theta.get_data()
|
||||
all_alpha_data = raw_alpha.get_data()
|
||||
all_beta_data = raw_beta.get_data()
|
||||
|
||||
ch_idx_clean = [raw_clean.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_theta = [raw_theta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_alpha = [raw_alpha.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_beta = [raw_beta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
|
||||
all_features = []
|
||||
all_labels = []
|
||||
run_numbers = []
|
||||
sample_offset = 0
|
||||
|
||||
for run_idx, run_num in enumerate(target_runs):
|
||||
if run_idx >= len(raw_runs):
|
||||
continue
|
||||
|
||||
annotations = annotations_runs[run_idx]
|
||||
run_length = run_lengths[run_idx]
|
||||
|
||||
if run_num in EXECUTION_RUNS:
|
||||
task_type = 'ME'
|
||||
elif run_num in IMAGERY_RUNS:
|
||||
task_type = 'MI'
|
||||
else:
|
||||
sample_offset += run_length
|
||||
continue
|
||||
|
||||
features_list, labels_list = _extract_run_features_from_arrays(
|
||||
all_raw_data, all_theta_data, all_alpha_data, all_beta_data,
|
||||
ch_idx_clean, ch_idx_theta, ch_idx_alpha, ch_idx_beta,
|
||||
annotations, task_type, sample_offset, all_raw_data.shape[1]
|
||||
)
|
||||
|
||||
if len(features_list) > 0:
|
||||
all_features.append(np.array(features_list))
|
||||
all_labels.append(np.array(labels_list))
|
||||
run_numbers.append(run_num)
|
||||
|
||||
sample_offset += run_length
|
||||
|
||||
return all_features, all_labels, run_numbers, n_kept
|
||||
|
||||
|
||||
def fit_global_ica(subject_list, target_runs=None, verbose=True):
|
||||
"""
|
||||
Fit ICA once on all subjects' broadband data concatenated.
|
||||
|
||||
Returns
|
||||
-------
|
||||
global_ica_results : dict with keys 'mixing', 'unmixing', 'kept_components'
|
||||
"""
|
||||
if target_runs is None:
|
||||
target_runs = TARGET_RUNS
|
||||
|
||||
all_raws = []
|
||||
|
||||
for subject_num in subject_list:
|
||||
for run_num in target_runs:
|
||||
try:
|
||||
signal_data = load_signal_file(subject_num, run_num)
|
||||
raw = create_mne_raw(signal_data)
|
||||
all_raws.append(raw)
|
||||
except Exception:
|
||||
continue
|
||||
|
||||
if len(all_raws) == 0:
|
||||
raise ValueError("No data loaded for global ICA")
|
||||
|
||||
if verbose:
|
||||
print(f" Global ICA: concatenating {len(all_raws)} runs...")
|
||||
|
||||
global_raw = mne.concatenate_raws(all_raws, preload=True)
|
||||
|
||||
if verbose:
|
||||
duration = global_raw.n_times / global_raw.info['sfreq']
|
||||
print(f" Global ICA: {duration:.0f}s total data")
|
||||
|
||||
# Fit ICA once on broadband data
|
||||
if verbose:
|
||||
print(f" Fitting global ICA on broadband data...")
|
||||
_, ica, kept = apply_fastica_denoising(global_raw, verbose=verbose)
|
||||
|
||||
return {
|
||||
'mixing': ica.mixing_matrix_,
|
||||
'unmixing': ica.unmixing_matrix_,
|
||||
'kept_components': kept,
|
||||
}
|
||||
|
||||
|
||||
def _apply_precomputed_ica(raw, ica_result):
|
||||
"""
|
||||
Apply a pre-fitted ICA decomposition to reconstruct cleaned signals.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
raw : mne.io.Raw
|
||||
ica_result : tuple (mixing, unmixing, kept_components)
|
||||
"""
|
||||
mixing, unmixing, kept_components = ica_result
|
||||
|
||||
if len(kept_components) == 0:
|
||||
return raw.copy()
|
||||
|
||||
raw_ica = raw.copy().pick(ICA_CHANNELS)
|
||||
raw_data = raw_ica.get_data()
|
||||
icasigs = unmixing @ raw_data
|
||||
|
||||
A_p = mixing[:, kept_components]
|
||||
S_p = icasigs[kept_components, :]
|
||||
reconstructed = A_p @ S_p
|
||||
|
||||
raw_clean = mne.io.RawArray(reconstructed, raw_ica.info, verbose=False)
|
||||
raw_clean.set_annotations(raw.annotations)
|
||||
return raw_clean
|
||||
|
||||
|
||||
# =============================================================================
|
||||
# Feature extraction helpers
|
||||
# =============================================================================
|
||||
|
||||
def _extract_run_features(raw_clean, raw_theta, raw_alpha, raw_beta,
|
||||
annotations, task_type):
|
||||
"""Extract Hjorth features from a single (non-concatenated) run."""
|
||||
features_list = []
|
||||
labels_list = []
|
||||
|
||||
ch_idx_clean = [raw_clean.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_theta = [raw_theta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_alpha = [raw_alpha.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
ch_idx_beta = [raw_beta.ch_names.index(ch) for ch in TARGET_CHANNELS]
|
||||
|
||||
# Pre-fetch full arrays ONCE (avoid repeated get_data() in loop)
|
||||
all_raw = raw_clean.get_data()
|
||||
all_theta = raw_theta.get_data()
|
||||
all_alpha = raw_alpha.get_data()
|
||||
all_beta = raw_beta.get_data()
|
||||
|
||||
for _, annot in annotations.iterrows():
|
||||
if annot['label'] not in ACTIVE_EVENT_LABELS:
|
||||
continue
|
||||
|
||||
start = int(annot['start_row'])
|
||||
end = int(annot['end_row'])
|
||||
end = min(end, all_raw.shape[1])
|
||||
if start >= end:
|
||||
continue
|
||||
|
||||
data_raw = all_raw[ch_idx_clean, start:end]
|
||||
data_theta = all_theta[ch_idx_theta, start:end]
|
||||
data_alpha = all_alpha[ch_idx_alpha, start:end]
|
||||
data_beta = all_beta[ch_idx_beta, start:end]
|
||||
|
||||
features = extract_epoch_features(data_raw, data_theta,
|
||||
data_alpha, data_beta)
|
||||
features_list.append(features)
|
||||
labels_list.append(task_type)
|
||||
|
||||
return features_list, labels_list
|
||||
|
||||
|
||||
def _extract_run_features_from_arrays(all_raw, all_theta, all_alpha, all_beta,
|
||||
ch_idx_clean, ch_idx_theta, ch_idx_alpha,
|
||||
ch_idx_beta,
|
||||
annotations, task_type, sample_offset,
|
||||
max_samples):
|
||||
"""Extract Hjorth features from one run within pre-fetched concatenated arrays.
|
||||
|
||||
This avoids repeated get_data() calls by working directly on numpy arrays.
|
||||
"""
|
||||
features_list = []
|
||||
labels_list = []
|
||||
|
||||
for _, annot in annotations.iterrows():
|
||||
if annot['label'] not in ACTIVE_EVENT_LABELS:
|
||||
continue
|
||||
|
||||
start = sample_offset + int(annot['start_row'])
|
||||
end = sample_offset + int(annot['end_row'])
|
||||
end = min(end, max_samples)
|
||||
if start >= end:
|
||||
continue
|
||||
|
||||
data_raw = all_raw[ch_idx_clean, start:end]
|
||||
data_theta = all_theta[ch_idx_theta, start:end]
|
||||
data_alpha = all_alpha[ch_idx_alpha, start:end]
|
||||
data_beta = all_beta[ch_idx_beta, start:end]
|
||||
|
||||
features = extract_epoch_features(data_raw, data_theta,
|
||||
data_alpha, data_beta)
|
||||
features_list.append(features)
|
||||
labels_list.append(task_type)
|
||||
|
||||
return features_list, labels_list
|
||||
|
||||
|
||||
# =============================================================================
|
||||
# Classification (Section 3.6)
|
||||
# =============================================================================
|
||||
|
||||
def classify_with_averaging(X_train, y_train, X_test, y_test,
|
||||
X_val=None, y_val=None, verbose=True):
|
||||
"""
|
||||
Train SVM N_RUNS times with different random seeds and report mean ± std.
|
||||
|
||||
Paper: "results were averaged by running the model five times"
|
||||
|
||||
Uses MinMaxScaler [0,1] per Equation 8, fitted on training data only.
|
||||
|
||||
Returns
|
||||
-------
|
||||
results : dict with keys like 'test_acc', 'val_acc', etc.
|
||||
Each value is a list of N_RUNS floats.
|
||||
"""
|
||||
# Normalize (Equation 8)
|
||||
scaler = MinMaxScaler(feature_range=(0, 1))
|
||||
X_train_s = scaler.fit_transform(X_train)
|
||||
X_test_s = scaler.transform(X_test)
|
||||
X_val_s = scaler.transform(X_val) if X_val is not None else None
|
||||
|
||||
results = {
|
||||
'train_acc': [], 'test_acc': [], 'val_acc': [],
|
||||
'test_me_recall': [], 'test_mi_recall': [],
|
||||
'val_me_recall': [], 'val_mi_recall': [],
|
||||
}
|
||||
|
||||
if verbose:
|
||||
print(f"\n Training SVM {N_RUNS} times (C={SVM_C}, gamma={SVM_GAMMA}, "
|
||||
f"kernel={SVM_KERNEL}, deflation ICA)")
|
||||
print(f" {'Run':>5} | {'Seed':>6} | {'Train':>7} | {'Test':>7} | "
|
||||
f"{'Val':>7} | {'Test ME':>8} | {'Test MI':>8}")
|
||||
print(f" {'-'*65}")
|
||||
|
||||
for run_i, seed in enumerate(RANDOM_SEEDS):
|
||||
svm = SVC(kernel=SVM_KERNEL, C=SVM_C, gamma=SVM_GAMMA,
|
||||
random_state=seed)
|
||||
svm.fit(X_train_s, y_train)
|
||||
|
||||
train_acc = accuracy_score(y_train, svm.predict(X_train_s))
|
||||
test_acc = accuracy_score(y_test, svm.predict(X_test_s))
|
||||
results['train_acc'].append(train_acc)
|
||||
results['test_acc'].append(test_acc)
|
||||
|
||||
# Per-class recall
|
||||
test_cm = confusion_matrix(y_test, svm.predict(X_test_s),
|
||||
labels=['ME', 'MI'])
|
||||
test_me = test_cm[0, 0] / test_cm[0].sum() if test_cm[0].sum() > 0 else 0
|
||||
test_mi = test_cm[1, 1] / test_cm[1].sum() if test_cm[1].sum() > 0 else 0
|
||||
results['test_me_recall'].append(test_me)
|
||||
results['test_mi_recall'].append(test_mi)
|
||||
|
||||
val_acc = 0
|
||||
val_me = 0
|
||||
val_mi = 0
|
||||
if X_val is not None:
|
||||
val_acc = accuracy_score(y_val, svm.predict(X_val_s))
|
||||
val_cm = confusion_matrix(y_val, svm.predict(X_val_s),
|
||||
labels=['ME', 'MI'])
|
||||
val_me = val_cm[0, 0] / val_cm[0].sum() if val_cm[0].sum() > 0 else 0
|
||||
val_mi = val_cm[1, 1] / val_cm[1].sum() if val_cm[1].sum() > 0 else 0
|
||||
|
||||
results['val_acc'].append(val_acc)
|
||||
results['val_me_recall'].append(val_me)
|
||||
results['val_mi_recall'].append(val_mi)
|
||||
|
||||
if verbose:
|
||||
print(f" {run_i+1:>5} | {seed:>6} | {train_acc:>7.2%} | "
|
||||
f"{test_acc:>7.2%} | {val_acc:>7.2%} | "
|
||||
f"{test_me:>8.2%} | {test_mi:>8.2%}")
|
||||
|
||||
return results
|
||||
|
||||
|
||||
def print_results_summary(results):
|
||||
"""Print mean ± std summary matching the paper's Table 6/7 format."""
|
||||
print(f"\n {'Metric':<28s} {'Mean ± Std':>14s}")
|
||||
print(f" {'-'*44}")
|
||||
|
||||
labels = {
|
||||
'train_acc': 'Training Accuracy',
|
||||
'test_acc': 'Testing Accuracy',
|
||||
'val_acc': 'Validation Accuracy',
|
||||
'test_me_recall': 'Test ME Recall (TP rate)',
|
||||
'test_mi_recall': 'Test MI Recall (TN rate)',
|
||||
'val_me_recall': 'Val ME Recall (TP rate)',
|
||||
'val_mi_recall': 'Val MI Recall (TN rate)',
|
||||
}
|
||||
|
||||
for key, label in labels.items():
|
||||
vals = np.array(results[key])
|
||||
print(f" {label:<28s} {vals.mean():>6.2%} ± {vals.std():.2%}")
|
||||
|
||||
print(f"\n Paper's Method 2 targets:")
|
||||
print(f" Overall accuracy: 68.8 ± 0.71%")
|
||||
print(f" ME recall: 68.17%")
|
||||
print(f" MI recall: 68.41%")
|
||||
245
reproduction_notebook.ipynb
Normal file
245
reproduction_notebook.ipynb
Normal file
@@ -0,0 +1,245 @@
|
||||
{
|
||||
"cells": [
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"# Reproducing: Mwata-Velu et al. (2023)\n",
|
||||
"\n",
|
||||
"**Paper**: \"EEG-BCI Features Discrimination between Executed and Imagined Movements Based on FastICA, Hjorth Parameters, and SVM\" \n",
|
||||
"**Journal**: Mathematics 2023, 11, 4409 \n",
|
||||
"**DOI**: https://doi.org/10.3390/math11214409\n",
|
||||
"\n",
|
||||
"## ICA Strategy\n",
|
||||
"\n",
|
||||
"The paper does not specify whether ICA is fitted per-run, per-subject, or globally.\n",
|
||||
"This notebook supports all three strategies via `config.ICA_STRATEGY`.\n",
|
||||
"Change it in `config.py` before running.\n",
|
||||
"\n",
|
||||
"## Key Implementation Decisions\n",
|
||||
"\n",
|
||||
"| Decision | Paper says | We do | Rationale |\n",
|
||||
"|----------|-----------|-------|----------|\n",
|
||||
"| Pipeline order | Figure 1: filter→ICA; Algorithm 1: ICA with internal sub-band eval | ICA then sub-band eval | Energy criterion is meaningless on pre-filtered data |\n",
|
||||
"| ICA algorithm | Gram-Schmidt (Algorithm 1, Step 3) | `algorithm='deflation'` | Deflation uses Gram-Schmidt |\n",
|
||||
"| Energy criterion | ∀χ ∈ {α, β, **γ**} | ∀χ ∈ {**θ**, α, β} | γ never defined; likely typo for θ |\n",
|
||||
"| ICA scope | Not specified | Configurable | Reproducibility variable |\n",
|
||||
"| Classification Method | Methods 1 and 2 | Method 2 only (cross-subject) | Method 1 split is contradictory |"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"## 1. Setup"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"import numpy as np\n",
|
||||
"import mne\n",
|
||||
"import warnings\n",
|
||||
"warnings.filterwarnings('ignore', category=RuntimeWarning) # MNE verbosity\n",
|
||||
"mne.set_log_level('WARNING')\n",
|
||||
"\n",
|
||||
"from config import (\n",
|
||||
" ICA_STRATEGY, DATA_DIR, TARGET_CHANNELS,\n",
|
||||
" TRAIN_SUBJECTS, TEST_SUBJECTS, VAL_SUBJECTS, TARGET_RUNS,\n",
|
||||
")\n",
|
||||
"from pipeline import (\n",
|
||||
" process_subject_per_run, process_subject_per_subject,\n",
|
||||
" process_subject_global, fit_global_ica,\n",
|
||||
" classify_with_averaging, print_results_summary,\n",
|
||||
")\n",
|
||||
"\n",
|
||||
"print(f\"Data directory: {DATA_DIR}\")\n",
|
||||
"print(f\"ICA strategy: {ICA_STRATEGY}\")\n",
|
||||
"print(f\"Target channels: {TARGET_CHANNELS}\")\n",
|
||||
"print(f\"Subjects: {len(TRAIN_SUBJECTS)} train, {len(TEST_SUBJECTS)} test, {len(VAL_SUBJECTS)} val\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"## 2. Process All Subjects (Method 2: Cross-Subject Split)\n",
|
||||
"\n",
|
||||
"Table 4 from the paper:\n",
|
||||
"- Training: Subjects 1-83 (80%)\n",
|
||||
"- Testing: Subjects 84-93 (10%)\n",
|
||||
"- Validation: Subjects 94-103 (10%)"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"# If using global ICA, fit it first on training subjects\n",
|
||||
"global_ica_results = None\n",
|
||||
"if ICA_STRATEGY == 'global':\n",
|
||||
" print(\"Fitting global ICA on all training subjects...\")\n",
|
||||
" global_ica_results = fit_global_ica(TRAIN_SUBJECTS)\n",
|
||||
" print(\"Global ICA fitting complete.\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"def process_subject_group(subject_list, group_name):\n",
|
||||
" \"\"\"Process a group of subjects and collect features/labels.\"\"\"\n",
|
||||
" all_features = []\n",
|
||||
" all_labels = []\n",
|
||||
" total_kept = 0\n",
|
||||
" n_processed = 0\n",
|
||||
" \n",
|
||||
" print(f\"\\n{'='*60}\")\n",
|
||||
" print(f\"PROCESSING {group_name} ({len(subject_list)} subjects)\")\n",
|
||||
" print(f\"{'='*60}\")\n",
|
||||
" \n",
|
||||
" for subject_num in subject_list:\n",
|
||||
" try:\n",
|
||||
" if ICA_STRATEGY == 'global':\n",
|
||||
" feats, labels, runs, n_kept = process_subject_global(\n",
|
||||
" subject_num, global_ica_results, verbose=True)\n",
|
||||
" elif ICA_STRATEGY == 'per_subject':\n",
|
||||
" feats, labels, runs, n_kept = process_subject_per_subject(\n",
|
||||
" subject_num, verbose=True)\n",
|
||||
" elif ICA_STRATEGY == 'per_run':\n",
|
||||
" feats, labels, runs, n_kept = process_subject_per_run(\n",
|
||||
" subject_num, verbose=True)\n",
|
||||
" \n",
|
||||
" if len(feats) > 0:\n",
|
||||
" combined_feats = np.vstack(feats)\n",
|
||||
" combined_labels = np.concatenate(labels)\n",
|
||||
" all_features.append(combined_feats)\n",
|
||||
" all_labels.append(combined_labels)\n",
|
||||
" total_kept += n_kept\n",
|
||||
" n_processed += 1\n",
|
||||
" \n",
|
||||
" n_me = np.sum(combined_labels == 'ME')\n",
|
||||
" n_mi = np.sum(combined_labels == 'MI')\n",
|
||||
" print(f\" S{subject_num:03d}: {len(combined_labels)} epochs \"\n",
|
||||
" f\"(ME={n_me}, MI={n_mi}), {n_kept} ICA components kept\")\n",
|
||||
" except Exception as e:\n",
|
||||
" print(f\" S{subject_num:03d}: ERROR - {e}\")\n",
|
||||
" continue\n",
|
||||
" \n",
|
||||
" if len(all_features) > 0:\n",
|
||||
" X = np.vstack(all_features)\n",
|
||||
" y = np.concatenate(all_labels)\n",
|
||||
" else:\n",
|
||||
" X = np.array([])\n",
|
||||
" y = np.array([])\n",
|
||||
" \n",
|
||||
" print(f\"\\n {group_name} total: {len(y)} samples \"\n",
|
||||
" f\"(ME={np.sum(y=='ME')}, MI={np.sum(y=='MI')})\")\n",
|
||||
" if n_processed > 0:\n",
|
||||
" print(f\" Avg ICA components kept: {total_kept / n_processed:.1f}\")\n",
|
||||
" \n",
|
||||
" return X, y"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"X_train, y_train = process_subject_group(TRAIN_SUBJECTS, \"TRAINING\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"X_test, y_test = process_subject_group(TEST_SUBJECTS, \"TESTING\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"X_val, y_val = process_subject_group(VAL_SUBJECTS, \"VALIDATION\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"# Summary\n",
|
||||
"print(f\"\\n{'='*60}\")\n",
|
||||
"print(f\"DATASET SUMMARY\")\n",
|
||||
"print(f\"{'='*60}\")\n",
|
||||
"print(f\" Training: {X_train.shape} — ME={np.sum(y_train=='ME')}, MI={np.sum(y_train=='MI')}\")\n",
|
||||
"print(f\" Testing: {X_test.shape} — ME={np.sum(y_test=='ME')}, MI={np.sum(y_test=='MI')}\")\n",
|
||||
"print(f\" Validation: {X_val.shape} — ME={np.sum(y_val=='ME')}, MI={np.sum(y_val=='MI')}\")\n",
|
||||
"print(f\"\\n Paper expects: ~6972 train, ~840 test, ~840 val\")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"## 4. Classification with 5-Run Averaging"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"results = classify_with_averaging(\n",
|
||||
" X_train, y_train,\n",
|
||||
" X_test, y_test,\n",
|
||||
" X_val, y_val,\n",
|
||||
")"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"print_results_summary(results)"
|
||||
]
|
||||
}
|
||||
],
|
||||
"metadata": {
|
||||
"kernelspec": {
|
||||
"display_name": "THESIS",
|
||||
"language": "python",
|
||||
"name": "thesis"
|
||||
},
|
||||
"language_info": {
|
||||
"codemirror_mode": {
|
||||
"name": "ipython",
|
||||
"version": 3
|
||||
},
|
||||
"file_extension": ".py",
|
||||
"mimetype": "text/x-python",
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.9.23"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
"nbformat_minor": 4
|
||||
}
|
||||
7
requirements.txt
Normal file
7
requirements.txt
Normal file
@@ -0,0 +1,7 @@
|
||||
mne>=1.6
|
||||
numpy>=1.24
|
||||
pandas>=2.0
|
||||
scipy>=1.11
|
||||
scikit-learn>=1.3
|
||||
matplotlib>=3.7
|
||||
seaborn>=0.12
|
||||
Reference in New Issue
Block a user