1D sampling (x or t axis)

By default, computed functions or data generated for the pseudo-file "+" are sampled over the entire range of the plot as set by a prior set xrange command, by an explicit global range specifier at the very start of the plot or splot command, or by autoscaling the xrange to span data seen in all the elements of this plot. However, individual plot components can be assigned a more restricted sampling range.

Examples:

This establishes a total range on x running from 0 to 1000 and then plots data from a file and two functions each spanning a portion of the total range:

      set xrange [0:1000]
      plot 'datafile', [0:200] func1(x), [200:500] func2(x)

This is similar except that the total range is established by the contents of the data file. In this case the sampled functions may or may not be entirely contained in the plot:

      set autoscale x
      plot 'datafile', [0:200] func1(x), [200:500] func2(x)

This command is ambiguous. The initial range will be interpreted as applying to the entire plot, not solely to the sampling of the first function as was probably the intent:

      plot [0:10] f(x), [10:20] g(x), [20:30] h(x)

This command removes the ambiguity of the previous example by inserting the keyword sample so that the range is not applied to the entire plot:

      plot sample [0:10] f(x), [10:20] g(x), [20:30] h(x)

This example shows one way of tracing out a helix in a 3D plot

      set xrange [-2:2]; set yrange [-2:2]
      splot sample [h=1:10] '+' using (cos(h)):(sin(h)):(h)