set output 'twocar_vel.ps' 
set term postscript color enhanced 'Helvetica,18'  
set style line 1 lt rgb 'red' lw 3  
set style line 2 lt rgb 'sea-green' lw 3  
set style line 3 lt rgb 'blue' lw 3  
set style line 4 lt rgb 'cyan' lw 3  
set style line 5 lt rgb 'violet' lw 3  
set grid 
set key top right 
set xlabel 'Time after car B hits the brakes (s)' 
set ylabel 'Velocity (m/s) ' 
plot [0:9.0][0:30]     './twocar_calc.out' using 1:3 with lines ls 1 lw 5 t 'car A'  ,    './twocar_calc.out' using 1:5 with lines ls 3 lw 5 t 'car B'  
set output 
quit 
