set xzeroaxis set xtics axis set xrange [-10:10] set arrow 1 from -9,0 to -10,0 set arrow 2 from 9,0 to 10,0 set yzeroaxis set ytics axis set yrange [-1:1] set arrow 3 from 0,-.9 to 0,-1 set arrow 4 from 0,.9 to 0,1 set border 0 plot sin(x)