set output 'phase_plot_a.ps' 
set term postscript color enhanced 'Helvetica,18'   
set style line 1 lt rgb 'red' lw 3  
set style line 2 lt rgb '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 bot left 
set ylabel 'Phase (degrees)'  
set xlabel 'Driving Frequency (rad/s)' 
set title 'F_{max} = 2.0 N, m = 0.1 kg, k = 7.5 N/m, b = 0.02 N/m/s' 
set label  '{/Symbol w_0} ' at 8.5,-5.5 
set arrow 1 from 8.66,0 to 8.66,180 nohead lt 0 lc -1 lw 3 
plot [0:20][0:180] './calc_phase.out' index 0 using 2:8         with points ls 1 ps 0.6 pt 3 t ''  
set output 
quit 
