GNUPlot Manual

36 SET-SHOW gnuplot 4.0 153
set zero
show zero
gnuplot will not plot a point if its imaginary part is greater in magnitude than the zero threshold.
This threshold is also used in various other parts of gnuplot as a (crude) numerical-error threshold.
The default zero value is 1e-8. zero values larger than 1e-3 (the reciprocal of the number of pixels in a
typical bitmap display) should probably be avoided, but it is not unreasonable to set zero to 0.0.
36.106 Zeroaxis
The x axis may be drawn by set xzeroaxis and removed by unset xzeroaxis. Similar commands
behave similarly for the y, x2, and y2 axes.
Syntax:
set {x|x2|y|y2|}zeroaxis { {linestyle | ls }
| { linetype | lt }
{ linewidth | lw }}
unset {x|x2|y|y2|}zeroaxis
show {x|y|}zeroaxis
By default, these options are off. The selected zero axis is drawn with a line of type
and width (if supported by the terminal driver currently in use), or a user-defined style
.
If no linetype is specified, any zero axes selected will be drawn using the axis linetype (linetype 0).
set zeroaxis is equivalent to set xzeroaxis; set yzeroaxis. set nozeroaxis is equivalent to unset
xzeroaxis; unset yzeroaxis.
Examples:
To simply have the y=0 axis drawn visibly:
set xzeroaxis
If you want a thick line in a different color or pattern, instead:
set xzeroaxis linetype 3 linewidth 2.5
36.107 Zlabel
This command sets the label for the z axis. Please see set xlabel (p. 147).
36.108 Zmtics
The set zmtics command changes tics on the z axis to months of the year. Please see set xmtics
(p. 148) for details.
36.109 Zrange
The set zrange command sets the range that will be displayed on the z axis. The zrange is used only
by splot and is ignored by plot. Please see set xrange (p. 148) for details.
36.110 Ztics
The set ztics command controls major (labelled) tics on the z axis. Please see set xtics (p. 149) for
details.