GNUPlot Manual

150 gnuplot 4.0 36 SET-SHOW
The defaults are border mirror norotate for tics on the x and y axes, and border nomirror norotate
for tics on the x2 and y2 axes. For the z axis, the {axis | border} option is not available and the
default is nomirror. If you do want to mirror the z-axis tics, you might want to create a bit more room
for them with set border.
set xtics with no options restores the default border or axis if xtics are being displayed; otherwise it
has no effect. Any previously specified tic frequency or position {and labels} are retained.
Positions of the tics are calculated automatically by default or if the autofreq option is given; otherwise
they may be specified in either of two forms:
The implicit , , form specifies that a series of tics will be plotted on the axis
between the values and with an increment of . If is not given, it is
assumed to be infinity. The increment may be negative. If neither nor is given,
is assumed to be negative infinity, is assumed to be positive infinity, and the tics will be drawn
at integral multiples of . If the axis is logarithmic, the increment will be used as a multiplicative
factor.
The set grid options ’front’, ’back’ and ’layerdefault’ affect the drawing order of the xtics, too.
Examples:
Make tics at 0, 0.5, 1, 1.5, ..., 9.5, 10.
set xtics 0,.5,10
Make tics at ..., -10, -5, 0, 5, 10, ...
set xtics 5
Make tics at 1, 100, 1e4, 1e6, 1e8.
set logscale x; set xtics 1,100,1e8
The explicit ("" , ...) form allows arbitrary tic positions or non-numeric tic
labels. In this form, the tics do not need to be listed in numerical order. Each tic has a position,
optionally with a label. Note that the label is a string enclosed by quotes. It may be a constant string,
such as "hello", may contain formatting information for converting the position into its label, such as
"%3f clients", or may be empty, "". See set format (p. 66) for more information. If no string is given,
the default label (numerical) is used.
An explicit tic mark has a third parameter, the "level". The default is level 0, a major tic. A level of 1
generates a minor tic. If the level is specified, then the label must also be supplied.
Examples:
set xtics ("low" 0, "medium" 50, "high" 100)
set xtics (1,2,4,8,16,32,64,128,256,512,1024)
set ytics ("bottom" 0, "" 10, "top" 20)
set ytics ("bottom" 0, "" 10 1, "top" 20)
In the second example, all tics are labelled. In the third, only the end tics are labelled. In the fourth,
the unlabeled tic is a minor tic.
However they are specified, tics will only be plotted when in range.
Format (or omission) of the tic labels is controlled by set format, unless the explicit text of a labels is
included in the set xtics () form.
Minor (unlabelled) tics can be added by the set mxtics command.
In case of timeseries data, position values must be given as quoted dates or times according to the format
timefmt. If the , , form is used, and must be given according
to timefmt, but must be in seconds. Times will be written out according to the format given
on set format, however.
Examples:
set xdata time
set timefmt "%d/%m"
set format x "%b %d"
set xrange ["01/12":"06/12"]
set xtics "01/12", 172800, "05/12"