Autoscaling may be set individually on the x, y or z axis or globally on all axes. The default is to autoscale all axes.
Syntax:
set autoscale {<axes>{min|max}}
set noautoscale {<axes>{min|max}}
show autoscale
where <axes> is either x, y, z, x2, y2 or xy. A keyword with min or max appended (this cannot be done with xy) tells gnuplot to autoscale just the minimum or maximum of that axis. If no keyword is given, all axes are autoscaled.
When autoscaling, the axis range is automatically computed and the dependent axis (y for a plot and z for splot) is scaled to include the range of the function or data being plotted.
If autoscaling of the dependent axis (y or z) is not set, the current y or z range is used.
Autoscaling the independent variables (x for plot and x,y for splot) is a request to set the domain to match any data file being plotted. If there are no data files, autoscaling an independent variable has no effect. In other words, in the absence of a data file, functions alone do not affect the x range (or the y range if plotting z = f(x,y)).
Please see set xrange for additional information about ranges.
The behavior of autoscaling remains consistent in parametric mode, (see set parametric). However, there are more dependent variables and hence more control over x, y, and z axis scales. In parametric mode, the independent or dummy variable is t for plots and u,v for splots. autoscale in parametric mode, then, controls all ranges (t, u, v, x, y, and z) and allows x, y, and z to be fully autoscaled.
Autoscaling works the same way for polar mode as it does for parametric mode for plot, with the extension that in polar mode set dummy can be used to change the independent variable from t (see set dummy).
When tics are displayed on second axes but no plot has been specified for those axes, x2range and y2range are inherited from xrange and yrange. This is done _before_ xrange and yrange are autoextended to a whole number of tics, which can cause unexpected results.
Examples:
This sets autoscaling of the y axis (other axes are not affected):
set autoscale y
This sets autoscaling only for the minimum of the y axis (the maximum of the y axis and the other axes are not affected):
set autoscale ymin
This sets autoscaling of the x and y axes:
set autoscale xy
This sets autoscaling of the x, y, z, x2 and y2 axes:
set autoscale
This disables autoscaling of the x, y, z, x2 and y2 axes:
set noautoscale
This disables autoscaling of the z axis only:
set noautoscale z