def remove_cycle_mrkr(self, epoch_start):
        """Remove cycle marker at epoch_start.

        Parameters
        ----------
        epoch_start: int
            start time of epoch, in seconds
        """
        if self.rater is None:
            raise IndexError('You need to have at least one rater')
        cycles = self.rater.find('cycles')
        for one_mrkr in cycles.iterfind('cyc_start'):
            if int(one_mrkr.text) == epoch_start:
                cycles.remove(one_mrkr)
                self.save()
                return

        for one_mrkr in cycles.iterfind('cyc_end'):
            if int(one_mrkr.text) == epoch_start:
                cycles.remove(one_mrkr)
                self.save()
                return

        raise KeyError('cycle marker at ' + str(epoch_start) + ' not found')
Remove cycle marker at epoch_start.

        Parameters
        ----------
        epoch_start: int
            start time of epoch, in seconds