! a vertical line at 10 and a labeled sloping line ! with no errors or warnings date "THE DATE STRING" legend "l1" "l2" "l3" "l4" mark x = 10 line = longshort xaxis "xaxis" yaxis "yaxis" plot "line label" x=1 y = 2 line = short data 1 2 3 4 5 6 7 8 9 10 11 12