set title "Fsteps plot\nwith date and time as x-values"
set style data fsteps
set xlabel "Date\nTime"
set timefmt "%d/%m/%y\t%H%M"
set yrange [ 0 : ]
set xdata time
set xrange [ "1/6/93":"1/11/93" ]
set ylabel "Concentration\nmg/l"
set format x "%d/%m\n%H:%M"
set grid
set key left
plot 'timedat.dat' using 1:3 t '', \
     'timedat.dat' using 1:3 t 'Total P' with points, \
     'timedat.dat' using 1:4 t '', \
     'timedat.dat' using 1:4 t 'PO4' with points 

Click here for minimal script to generate this plot

#
# Note: this demo exercises features introduced in version 4.6.5
#
set title "Time data on Y, microsecond precision" font ",14"
set ydata time
set timefmt "%s"
set offset 0.5,1.5,.2,.2
unset key

fulltime(col) = strftime("%d %b %Y\n%H:%M:%.3S",column(col))
parttime(col) = strftime("%H:%M:%.3S",column(col))

plot '-' using 0:1:(fulltime(1)):xticlabels(2):yticlabels(parttime(1)) \
         with labels point pt 7 left offset 1,1 font ",7"
1390852607.1	A
1390852607.2	B
1390852607.4	C
1390852607.8	D
1390852608.4	E
1390852610.001	F
e


Click here for minimal script to generate this plot