How to draw a rectangle in gnuplot, the easy way:

set object rect from 0,0 to 1,4

How to draw a rectangle in gnuplot:

set parametric

set samples 5

set xrange [-2:10]

set yrange [-2:10]

plot [0:2*pi] sin(t+pi/4)/1.414214+0.5,3*cos(t+pi/4)/1.414214+1.5

this will draw a recktangle of 1×3 with the lower left corner at (0,0)