What?

• GnuPlot allows to generate 2D and 3D plots of functions and data.
• It is a command-line program.
• You can run it on Windows, Mac or Linux and it is free.

When?

• When you need something very specific.
• When you need to automize the process.

The First Commands to Know

• set terminal [options]

  set output [options]

  it defines the output format.

• set xrange [options]

  set yrange [options]

  it defines the ranges of the function to plot.

• plot [options]

  the main command which draws the function or data.

The "plot" Command

• plot sin(x)

  to plot a classic math function.

• plot  "data.txt" using 1:2

  to plot data from a CSV file.

• plot  "data.txt" using 1:5 title 'My data' with linespoints linewidth 2 pointinterval -100 
        pointtype 13 pointsize 1 linecolor rgb "#228B22"

  a more customized version.

Example

# First, we tell to gnuplot what it the output
# Here, it is a SVG file called "output.svg", with a "times new roman" font
set terminal svg size 1473,824 enhanced fname 'Times New Roman' fsize 24 butt solid
set output 'output.svg'

# We define where to place the legend
set key inside bottom right
# Put a title to the x-axis
set xlabel 'Time'
# And a title to the y-axis
set ylabel 'Number of Logistics Service Provider'
# And the main title
set title 'Strategies Adoption'
# Eventually we plot the four curves
plot  "data.txt" using 1:5 title 'Strategy 1' with linespoints lw 2 pi -100 pt 13 ps 1 lc rgb "#228B22",\
      "data.txt" using 1:4 title 'Strategy 2' with linespoints lw 2 pi -100 pt 9 ps 1 lc rgb "#FF8C00",\
      "data.txt" using 1:2 title 'Strategy 3' with linespoints lw 2 pi -100 pt 11 ps 1 lc rgb "#003B6F",\
      "data.txt" using 1:3 title 'Strategy 4' with linespoints lw 2 pi -100 pt 7 ps 1 lc rgb "#CC0000"
						

Example

Figure 1: The output

Some links

• Gnuplot's official website.
• Gnuplot it online!
• Desmos : It is not Gnuplot, but it is useful.