def _read_record(self, f, blk, chans):
        """Read raw data from a single EDF channel.

        Parameters
        ----------
        i_chan : int
            index of the channel to read
        begsam : int
            index of the first sample
        endsam : int
            index of the last sample

        Returns
        -------
        numpy.ndarray
            A vector with the data as written on file, in 16-bit precision
        """
        dat_in_rec = empty((len(chans), self.max_smp))

        i_ch_in_dat = 0
        for i_ch in chans:
            offset, n_smp_per_chan = self._offset(blk, i_ch)

            f.seek(offset)
            x = fromfile(f, count=n_smp_per_chan, dtype=EDF_FORMAT)

            ratio = int(self.max_smp / n_smp_per_chan)
            dat_in_rec[i_ch_in_dat, :] = repeat(x, ratio)
            i_ch_in_dat += 1

        return dat_in_rec
Read raw data from a single EDF channel.

        Parameters
        ----------
        i_chan : int
            index of the channel to read
        begsam : int
            index of the first sample
        endsam : int
            index of the last sample

        Returns
        -------
        numpy.ndarray
            A vector with the data as written on file, in 16-bit precision