set output 'grid_para_c.ps' 
set term postscript color '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 bot right 
set ylabel 'Sum of squares of differences {/Symbol b} ' 
set xlabel 'Guessed value of parallax {/Symbol v} (milliarcsec)' 
plot [290:320][0.88e6:0.89e6] 'fit_gxand_para_c.dat' using ($7-0):($2-0)       with points ls 1 pt 3.0 ps 0.6 t ''  
set output 
quit 
