def _compute_seq_start_inds(self):
        """Compute sequence start indices.

        Returns
        -------
        np.ndarray :
            Array of shape (n_sequences,) containing the indices of the first
            windows of possible sequences.
        np.ndarray :
            Array of shape (n_sequences,) containing the unique file number of
            each sequence. Useful e.g. to do self-ensembling.
        """
        end_offset = 1 - self.n_windows if self.n_windows > 1 else None
        start_inds = (
            self.info["index"]
            .apply(lambda x: x[: end_offset : self.n_windows_stride])
            .values
        )
        file_ids = [[i] * len(inds) for i, inds in enumerate(start_inds)]
        return np.concatenate(start_inds), np.concatenate(file_ids)
Compute sequence start indices.

        Returns
        -------
        np.ndarray :
            Array of shape (n_sequences,) containing the indices of the first
            windows of possible sequences.
        np.ndarray :
            Array of shape (n_sequences,) containing the unique file number of
            each sequence. Useful e.g. to do self-ensembling.
        
braindecode/samplers/base.py