The installation of McStas seems rather complex. How should I
Have a look at the Quick
Install or the Official
Install Instructions. We provide a Windows installer for MS Windows
users, a debian package for installation on Ubuntu systems, and a dmg
installer for MacOSX users. A manual installation can be done using the
If you really can not manage, the McStas
LiveDVD provides a fully functional system for all Intel/AMD based
systems, without touching your local machine, but with full computing
I have updated my system. How do I reconfigure McStas without
reinstalling it ?
On Linux systems, execute (in administrator mode) the MCSTAS/tools/perl/mcstas_reconfigure
On Windows machines, the mcconfig.pl tool can do that as
The installation of McStas cannot find the right Perl interpreter.
What can I do?
Set the environment variable PERL to the full path of the Perl
interpreter to use before running ./configure:
rm -f config.cache # Remove cache of old choices setenv PERL /full/path/to/perl5 ./configure
How do I make PgPerl work on Red Hat/Suse/Debian/... Linux so that
I can use the graphical front-ends?
In Debian, PgPerl is included in
the distribution. Use dselect, synaptic, apt, or dpkg to install it
from your CD or from the network.
For Red Hat Linux and other
distributions that use the RPM format, binary packages might be
available for the Intel i386 (IBM PC compatible) architecture at http://www.rpmseek.com.
Installing from perl-PGPLOT source migh be tedious. We have set up
an automatic procedure for that (that may fail). From the McStas
distribution, try a:
./configure; sudo make install-pgplot; ./configure
If you compile yourself from source code:
Make sure that PGPLOT is properly installed, including the C
On some of the old Linux distributions, the library previously
"libf2c" has been renamed to "libg2c", but PgPerl may still wrongly
pick up the previous, old version. You can try to edit the makefile
(after "perl Makefile.PL", but before "make") to change all occurences
of "f2c" into "g2c". This problem is supposed to be fixed in a later
PgPerl release (around 2.15).
How do I make the graphical user interface use another C compiler?
The C compiler to use, as well as any special options needed for
optimization etc, can be specified during installation using the
enviroment variables CC and CFLAGS. For
setenv CC /usr/opt/ansic/cc setenv CFLAGS +O ./configure
It may be necessary to remove the file config.cache first
to override any choices made by configure during a previous install.
instructions in the distribution
It is also possible to define the MCSTAS_CC and MCSTAS_CFLAGS
environement variables to override the default configuration, or to
simply set it in the mcgui Preferences.
I can not write bigger files than 2Gb with McStas, is there a
First, please consider if you really need such big
files. If you do, McStas can perfectly well write bigger files than 2Gb
if you make sure that your MCSTAS_CFLAGS
contains proper c-compiler defines to allow this. On x86 Linux with
gcc, relevant values are
I think McStas gives the wrong number of neutrons in the detector
in my simulation. What is wrong?
The number of neutrons histories that reach the detector in a McStas
simulation is usually not very meaningful. McStas uses weighted
extensively (see the manual for details) and
different neutrons may carry widely different weights. Always use the
intensity in detectors when analyzing simulation data.
Can McStas use clusters and Grids ?
Yes, install MPICH or OpenMPI, reconfigure McStas (see above) and
select MPI or Grid when running the simulation from the GUI.
Can McStas import files from other neutron MC packages ?
Yes, McStas can read files generated by Vitess, MCNP/MCNPX, and
Tripoli. Other importers are easy to write. Just ask us.
What type of data can McStas generate ?
McStas usually generates histograms (tallies) as formatted (easy to
read) text files. Such text files may be read by the McStas internal
plotter using PGPLOT, but also using Matlab, Scilab, VRML/HTML (web
page), HDF/NeXus, XML/NeXus, Octave, IDL and more... Event files may be
generated for MCNP/MCNPX, Vitess and Tripoli. McStas has also its own
event file format, which can be used to split a simulation into pieces
(see the User Manual with the Virtual_input/output
Is there a way to interact with a running simulation ?
Yes, it is possible to make the simulation report and save results
during the simulation. The on-line plotting tool mcdaemon may then plot the results
as they come, in the course of the computation (see the Progress_bar component). On
Unix/Linux/MacOSX systems (excet when running with MPI and grids), one
may additionally send USR1 and USR2 signals to the simulation (refer to
the User Manual).
Mar 31, 1999.