The particle trajectories can be plotted in the Viewer by using the global history file ("ghis" by default) as a macro. Click on om the hand-set or ‘ on the tool bar. On the dialog that opens, enter the name of the global history file as the Macro file and click ‘OK’ to run it. All the tracks in the file will be read and displayed as Viewer streamlines. They can then be turned on and off through the Streamline Management Dialog.

To plot individual tracks from the history file, create a macro file which contains the lines:

where filename is the name of the history file, and n is the number of the track to draw. If m is present, all tracks in the range m-n will be drawn.

The track unpacking program, UNPACK, is run by clicking on Run, Utilities, GENTRA track unpacker. This is required to create individual history files for plotting in AUTOPLOT, but is NOT needed for the Viewer.

* Start the track unpacker as described above.

The track unpacker assumes that the name of the global history file has not been changed from the default name ("ghis"). The single-character identifiers for the names of the individual history and trajectory files must now be specified. Typing "none" will deactivate the production of one or other (or both) of the file types.

* In this example, we may want only history files (for viewing in AUTOPLOT) so type "none h" to prevent creation of trajectory files and to indicate that the name of the history files are to commence with "h".

The particular tracks for which files are to be produced must now be specified. These files can be specified by the individual track number (e.g. 3-4). Combinations of numbers and range up to a maximum of 20 inputs can be accepted (e.g. 1 3 5-7 10-12 14).

* Continuing with the worked example for which five tracks are produced, if we want to produce history files for tracks 1, 3 and 4 we can input 1 3 4 or 1 3-4.

The resulting history files, called h00001, h00003 or h00004 can now be plotted in AUTOPLOT.

If trajectory files are produced, a GENUSE file which plots them will also be written.

The global history file, ghis, will be automatically saved as ‘case.his’, by clicking on File, Save as a case. The genuse file will be saved as ‘case.gen’. The individual trajectory and history files will not be saved automatically. They can always be recovered from ghis by running the track unpacker, as described above.