Plotting a basic function
will plot the function x3-4x2+sin(x)/x.
gnuplot> plot x**3-4*x**2+sin(x)/x
Disabling the function label/legend on the top right
Will remove the label in the top right corner of the output and redraw the graph.
gnuplot> unset key gnuplot> replot
Outputting to pdf
Will create a new file called somefile.pdf, write it's output to it (that's what the replot command is for) and finally close the file so you can open it (
gnuplot> set terminal pdf Terminal type set to 'pdfcairo' Options are ' size 5.00in, 3.00in ' gnuplot> set output "somefile.pdf" gnuplot> replot gnuplot> unset output
If you prefer outputting to png or jpg, just use
set terminal png and set the output accordingly.
Restoring the output to standard after writing to pdf
gnuplot> set terminal pop restored terminal is wxt 0
Only plotting a certain domain
gnuplot> plot [x=-1:1] x**3
Drawing the x-axis
gnuplot> set xzeroaxis gnuplot> replot
Setting the axis labels
gnuplot> set ylabel "data" gnuplot> set xlabel "time" gnuplot> replot
That should be enough to get you started. If you'd like to know more, just check out the documentation for gnuplot.