Gnuplot

• gnuplot FAQ
• Using gnuplot
• gnuplotting
• demo printing values on top of the histogram columns
• http://galileo.phys.virginia.edu/compfac/courses/geek-hours/gnuplot.htmlloads of complex graph forms (physics)
• gnuplot demo index on sourceforge
• gantt chart demo
• plot of 'sar' output - ibm.com

Treat x axis as date/time (epoch)

set xdata time
set timefmt "%s"
  -  set xtics 3600
set format x "%H:%M:%S" # or whatever
plot ...