#!/usr/bin/gnuplot

set terminal x11

set size square
set grid xtics ytics
set style fill transparent

h_xmargin=8
h_ymargin=8

xr = h_xmargin * 2
yr = h_ymargin * 2

set xrange[-xr:xr]
set yrange[-yr:yr]
set xtics 1
set ytics 1

vec(a, b) = a - b
ex(t) = h_xmargin * cos(t)
ey(t) = h_ymargin * sin(t)

set parametric

plot ex(t),ey(t) title '', \
    'gnuplot.out' using 1:2:(vec($4, $1)):(vec($5,$2)) with vectors
pause -1