noextend

     set autoscale noextend

By default autoscaling sets the axis range limits to the nearest tic label position that includes all the plot data. Keywords fixmin, fixmax, fix or noextend tell gnuplot to disable extension of the axis range to the next tic mark position. In this case the axis range limit exactly matches the coordinate of the most extreme data point. set autoscale noextend is a synonym for set autoscale fix. Range extension for a single axis can be disabled by appending the noextend keyword to the corresponding range command, e.g.

     set yrange [0:*] noextend

set autoscale keepfix autoscales all axes while leaving the fix settings unchanged.