The refresh command is similar to replot, with two major differences. refresh reformats and redraws the current plot using the data already read in. This means that you can use refresh for plots with inline data (pseudo-device '-') and for plots from datafiles whose contents are volatile. You cannot use the refresh command to add new data to an existing plot.
plot 'datafile' volatile with lines, '-' with labels 100 200 "Special point" e # Various mousing operations go here set title "Zoomed in view" set term post set output 'zoom.ps' refresh