(ov) overlay file, former version

The former version of the overlay-file command is still present as ov. ``o'' stands for ``old''. This command loads a file, changes the current buffer, and plots (in blue) the new data set over the former current buffer (in yellow), whithout recomputing the limits of the plot (unlike the new overlay command). This can be repeated to plot multiple data sets.

The commands ov1, ov2 and ov3 are also available load SWV data.

See also the new overlay command and mark command.