def untrim(self, n='all'):
        """
        Removes xmin, xmax, ymin, and ymax. 
        
        Parameters
        ----------
        n='all'
            Which data set to perform this action upon. 'all' means all data
            sets, or you can specify a list.
        """
        if len(self._set_xdata)==0 or len(self._set_ydata)==0:
            self._error("No data. Please use set_data() and plot() prior to zooming.")
            return

        if   _s.fun.is_a_number(n): n = [n]
        elif isinstance(n,str):     n = list(range(len(self._set_xdata)))

        # loop over the specified plots
        for i in n:
            self['xmin'][i] = None
            self['xmax'][i] = None
            self['ymin'][i] = None
            self['ymax'][i] = None
            
        # now show the update.
        self.clear_results()
        if self['autoplot']: self.plot()
        return self