TRAX FAQ: How to ...


The examples shown here suppose that TRAX has correctly been setup, in particular the necessary environment variables (such as $TRAX) point to the correct locations.

[ ... evaluate an axial dose distribution
| ... evaluate microdosimetric distributions
| ... evaluate energy and angular spectra of e- emitted from a medium
| ... simulate development of chemical species after irradiation
| ... evaluate a radial dose distribution
| ... evaluate an r-z dose distribution
| ... evaluate a "spherical" dose distribution
| ... evaluate a time-energy spectrum
| ... evaluate deposited energy spectra
| ... evaluate line track simulations
| ... evaluate point track simulations
| ... supply a user evaluation function
| ... run parallel simulations
| ... evaluate per trackfile vs on-the-fly ]


... evaluate an axial dose distribution

Also known as depth dose distribution. Run
   exec $TRAX/TUTOR/evaladose.exec
or
   exec $TRAX/TUTOR/evaladose.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate microdosimetric distributions

Also known as y-distribution and z-distribution. Run
   exec $TRAX/TUTOR/evalmdose.exec
or
   exec $TRAX/TUTOR/evalmdose.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate energy and angular spectra of e- emitted from a medium

Run
   exec $TRAX/TUTOR/evalout.exec
or
   exec $TRAX/TUTOR/evalout.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... simulate development of chemical species after irradiation

A simple case:
   exec $TRAX/TUTOR/dboxy.exec '' noxy '' '' e- 999 1000 0
This will calculate the development of radicals after the passage of a 999 keV electron, averaging 1000 primary electrons. The output will be the G-value as a function of time, stored in a gd-file.
Note that this a simple demo, producing a few ten thousand initial OH-radicals, which takes a few hundred seconds to calculate.
For being statistically significant, on the order of at least 100000 initial OH-radicals will be necessary.

... evaluate a radial dose distribution

Run
   exec $TRAX/TUTOR/evalrdose.exec
or
   exec $TRAX/TUTOR/evalrdose.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate an r-z dose distribution

Run
   exec $TRAX/TUTOR/evalrzdose.exec
or
   exec $TRAX/TUTOR/evalrzdose.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate a "spherical" dose distribution

Example:
   exec $TRAX/TUTOR/evalspheredose.exec '' keV00100 1 10000 0.10E-4
Simulates the dose distribution of 10000 electrons of 1 keV energy emitted from a point source. Results are recorded up to 0.10E-4 cm and placed in file evalspheredose.keV00100.gd

... evaluate a time-energy spectrum

Run
   exec $TRAX/TUTOR/evaltespc.exec
or
   exec $TRAX/TUTOR/evaltespc.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate deposited energy spectra

This is an example for a volmode evaluation. Running:
   exec $TRAX/TUTOR/evalvolmode.exec '/tmp/'  00500 500 30
will accumlate the energy spectrum of 500 electrons of 00500E1 keV (== 5 MeV) electrons emitted under 30 degree within a box.

... evaluate line track simulations

Running:
   exec $TRAX/TUTOR/linetrack.exec
or
   exec $TRAX/TUTOR/linetrack.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... evaluate point track simulations

Running:
   exec $TRAX/TUTOR/pointtrack.exec
or
   exec $TRAX/TUTOR/pointtrack.exec '/tmp/'
The second example will place the output files in the /tmp directory.

... supply a user evaluation function

Run
   exec $TRAX/TUTOR/evalusr.exec
or
   exec $TRAX/TUTOR/evalusr.exec '/tmp/' -64
The second example will build the user function in 64-bit mode and will place the output files in the /tmp directory.

... run parallel simulations

At present reasonably well supported only for the evalrcal command. Two different modes are possible: Multithreading on a single computer or independent runs distributed on a compute cluster. Both have advantages and drawbacks. In particular it has to be ensured that the random number sequence is unique for each parallel run, i.e. each run starts with a different seed and the sequences do not overlap.


... evaluate per trackfile vs on-the-fly

Run
   exec $TRAX/TUTOR/dblmd.exec
or
   exec $TRAX/TUTOR/dblmd.exec '/tmp/'
The second example will place the output files in the /tmp directory.
Last updated: M.Kraemer,
$Id: traxhowto.html,v 1.7 2026/01/20 21:53:32 kraemer Exp $