Input file for DirAx
DirAx is a program for indexing of single crystal data as explained in
Duisenberg, A.J.M.(1992). J. Appl. Cryst. 25, 92-96
(IUCR journal webpage)
Differences in the actual versions with respect to this article can be
found in the remarks page.
On a separate page you can find instructions
for obtaining and installing DirAx.
In most cases DirAx will run automatically with the default parameters.
To unravel obstinate problems some familiarity with the method is desirable.
We therefore recommend to practice with the example .drx files first
(see examples. If
problems cannot be solved properly (even after you have read the
manual) there may somezing be wronk with your copy of DirAx,
or you are doing something we did not anticipate.
First a line with the wavelength in Å.
Then you provide up to 1000 lines with 3 bisecting angles
theta, phi and chi (°) optionally followed by the
Alternatively you can provide 1000 lines with C-vectors (Å),
optionally followed by the intensity.
Example of a drx input file (this is example 1):
- Do not change the sequence of phi and chi
- Do not mix bisecting angles and C-vectors.
- Please be aware that the results of DirAx are expressed in the same
righthanded Cartesian XYZ system (origin always on the crystal)
that you have chosen for the input data. Our choice is Z vertical
(to Zenith), X to source (to Xray), and Y to complete the
- DirAx recognizes automatically whether bisecting angles or C-vectors are
- FORTRAN free format, neat columns as in the example are not necessary. Any
sensible number of decimals.
- The "intensity" is just for the record and is
not used as such, you may give it a different meaning or set it to 0.
16.05 118.42 30.40 471.2
14.06 -177.41 33.99 1819.7
15.58 -101.99 24.06 14093.5
16.05 116.80 25.73 6468.4
17.30 147.79 21.32 3638.7
10.37 140.39 55.14 2599.9
16.38 -173.91 54.41 1072.7
22.32 11.97 50.49 819.5
15.60 -142.60 15.09 3904.5
9.37 -78.08 9.79 442.6
17.27 58.49 58.52 1432.2
21.09 140.40 55.15 2151.4
24.20 -157.93 49.38 11920.9
23.94 -122.19 49.20 300.2
23.96 22.55 31.30 13966.5
24.40 129.37 27.68 198.5
24.40 127.77 24.92 3312.0
18.17 -51.75 12.45 1452.5
16.05 120.88 9.40 492.7
16.41 -1.54 10.47 1018.5
25.62 -21.63 47.89 2855.0
25.52 -135.42 34.69 699.1
25.68 -75.50 27.95 601.4
18.00 95.29 7.12 6772.5
16.70 31.45 4.71 21815.0
DirAx input files should have extension .drx. If a different extension
is used, the full name must be supplied. Similarly if the file is not
located in the current directory.
By typing help at the Dirax prompt, a webbrowser
(firefox, mozilla, netscape) is
started to display this documentation. If you want to use another
browser, you must store the name in the environment variable BROWSER
or define the browser with
\alias browser yourbrowser.
A description of all commands can be found here.
Many practical cases are explained in the examples
The original version of DirAx (still available) was written in Borland
Turbo Pascal 5.5 for DOS and compatibles by A.J.M. Duisenberg. It was
translated into Fortran (for VMS and Unix compatibles) by A.M.M. Schreurs.
- The cell reduction in DirAx is based upon Krivy, I. & Gruber,
B. (1976). Acta Cryst. A32, 297-298, but simplified (written in
vector form) and demanding less steps.
- We adopted the sorting algorithm HeapSort from the recommendable book:
William H. Press, Brian P. Flannery,
Saul A. Teukolsky, William T. Vetterling:
Numerical Recipes, Cambridge University Press; 1986.
- QuickSort was extracted from:
Robert Sedgewick: Algorithms, Addison-Wesley Publishing Company; 1983.
- You may not copy DirAx neither the auxiliary files except for
use by yourself or for use in your laboratory, institute, office
and the like.
- You may not hand over DirAx in any form to third parties
without provable permission from the author.
- You use DirAx at your own responsibility completely.
- Guarantee: Please do report failures, give comments and ask questions,
preferable via e-mail
we will help you as much as possible.
- Laboratory for Crystal and Structural Chemistry,
Bijvoet Center for Biomolecular Research,
NL-3584 CH Utrecht,
- If you feel DirAx was essential for solving your (indexing) problems you
might refer to:
Duisenberg, A.J.M.(1992). J. Appl. Cryst. 25, 92-96.