def read_data(self, f_start=None, f_stop=None,t_start=None, t_stop=None):
        """ Read data
        """

        self._setup_selection_range(f_start=f_start, f_stop=f_stop, t_start=t_start, t_stop=t_stop)

        #check if selection is small enough.
        if self.isheavy():
            logger.warning("Selection size of %.2f GB, exceeding our size limit %.2f GB. Instance created, header loaded, but data not loaded, please try another (t,v) selection." % (self._calc_selection_size() / (1024. ** 3), self.MAX_DATA_ARRAY_SIZE / (1024. ** 3)))
            self.data = np.array([0],dtype=self._d_type)
            return None

        #Convert input frequencies into what their corresponding channel number would be.
        self._setup_chans()
        #Update frequencies ranges from channel number.
        self._setup_freqs()

        self.data = self.h5["data"][self.t_start:self.t_stop,:,self.chan_start_idx:self.chan_stop_idx]
Read data