Xtics

Very fine control of the x axes tic marks is possible with the set xtics and set noxtics command. The x-axis tic marks may be turned off with the set noxtics command. They may be turned on (the default state) with set xtics. If you prefer your own series of tic marks, you may use the form
         set xtics <start>, <incr>{, <end>}
The curly braces indicate that the <end> parameter is optional. This command specifies that a series of tics will be plotted on the x axis between the x values <start> and <end> with an increment of <incr>. If <end> is not given it is assumed to be infinity. The increment may be negative. Example:
          set xtics 0,.5,10
makes tics 0, 0.5, 1, 1.5, ..., 9.5, 10. If you need arbitrary tic positions, or non-numeric tic labels, any non-empty set of tic positions and labels may be given with this format:
         set xtics ({"label"} pos {, {"label"} pos}...)
Again curly braces contain optional components. Thus, a set of tics are a set of positions, each with its own optional label. Note that the label is a string enclosed by quotes, and may be a constant string, such as ``hello'', or contain formatting information for the tic number (which is the same as the position), such as ''%3f clients''. See set format for more information about this case. The label may even be empty. Examples:
         set xtics ("low" 0, "medium" 50, "high" 100)
         set xtics (1,2,4,8,16,32,64,128,256,512,1024)
         set xtics ("bottom" 0, "" 10, "top" 20)
Tics will only be plotted when in range. The set ytics and set noytics commands work identically. See also set format command.