The diff command compares vectors in different plots.
diff plot1 plot2 [vecname ...]The command will compare all the vectors in the specified plots, or only the named vectors if any are given. If there are different vectors in the two plots, or any values in the vectors differ significantly, the difference is reported. The variables diff_abstol, diff_reltol, and diff_vntol are used to determine if two values are ``significantly'' different.