Multiple files in gnuplot

Seems obvious now but you can use paste

e.g.

plot "< paste file1.dat file2.dat" using 1:($2/$4) w points

Searching for tabs with grep

I was trying to search for an integer number, which had tabs after is
i.e grep 300 and it would come up with something like
300 -0.0137598 -0.00228325 0.930859 0.932037 -1.04561e+27 -1.73505e+26 7.07363e+28 7.08259e+28 -0.0129162 -0.00224769 0.874459 0.875568 0.00575037 0.00194563 -0.395375 0.396846 1.46282e+24
450 -0.00449249 -0.00663059 0.858427 0.869783 -3.41386e+26 -5.03861e+26 6.52322e+28 6.60951e+28 -0.00415084 -0.00613002 0.795084 0.805603 0.00124869 0.00187794 -0.257016 0.262097 1.46282e+24
etc....


i.e. where there is 300 within any number. To search for 300 i used
grep 300[[:space:]]