! grep '##' tt.dat | sed -e 's/##//' > tt1.dat
set multi
set noytic
p "tt.dat" w d
#
set yra [0:41]
set nokey 
p "tt1.dat"u 1:6  w linesp 3 3
#
set ytic
set origin 0.89, 0.0
p "tt1.dat"u 1:6  w d 7 7
#
set nomulti
pause -1