Download Atomic Laboratory for Interactive Numerical Experiments

that of a canonical ensemble where the average temperature remains under
user’s control. All the parameters of the thermostat can be varied through
graphical interfaces, which are described in next section. All energies, as
well as temperature, are measured in the energy scale ǫ – of the first materials in case there are two types of materials – and analogously for lengths,
which are measured in units of σ. The time unit is chosen in such a way to
make the rescaled mass in Eq. (7) equal to one.
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Source files
The basic structure of ALINE is basically unchanged respect to the 2D version
[1] and is represented in Fig. 3. Also the names of the files and procedures
are either the same ones or similar ones. The program is written in C and
developed for an X11 Window System platform. The program windows and
all graphics are based on the MOTIF library [9]. The program source files
are four C files and the corresponding interfaces, together with the additional
interface file initial.h for some initial settings. The source files are listed
in Table 1.
• The main file is graphics.c. This file also manages all the graphical
windows, that is the main graphical window, Fig. 1, and all the other
windows than can be open by the user from the main window. All the
graphical windows represent communication channels from program
to user, passing information both in graphical and text format.
• On the other hand, the actual communication channels from user to
program are represented by the various buttons and similar widgets
in the windows and are managed by the file callback.c. They allow
the user e. g. to select a particular initial configuration and modify the
visualization mode and the system parameters.
• The preparation of the initial configuration, together with all its possible variants, is carried out by the procedures in the file calc.c.
• Finally, time evolution during a single generic time step is carried out
in the file simu.c, whose procedures are called by the main program
every time step.
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