Availability Up-to-date information on which versions of VisIt are running on which NERSC platforms is available at: NERSC Visualization Software Applications.
module load gnuplot gnuplotto load and run gnuplot.
helpat the Gnuplot command prompt. After that, keep looking through the keywords. Good starting points are 'plot' and 'set', e.g.,
help plot
load 'simple.dem'at the Gnuplot command prompt.