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c CCLRC
Section 4.1
4.1
Constructing DL POLY 3 : an Overview
4.1.1
Constructing the Standard Version
DL POLY 3 was designed as a package of useful subroutines rather than a single program, which
means that users are to be able to construct a working simulation program of their own design
from the subroutines available, which is capable of performing a specific simulation. However, we
recognise that many, perhaps most, users will be content with creating a standard version that
covers all of the possible applications and for this reason we have only provided the necessary tools
to assemble such a version. The method of creating the standard version is described in detail in
this chapter, however a brief step-by-step description follows.
1. DL POLY 3 is supplied as a UNIX compressed file (tarred and gzipped). This must uncom-
pressed and un-tared to create the DL POLY 3 directory (Section
1.4
).
2. In the build subdirectory you will find the required DL POLY 3 makefiles (see Section
4.2.1
and Appendix
C
, where the main Makefiles are listed). This must be copied into the subdirec-
tory containing the relevant source code. In most cases this will be the source subdirectory.
3. The chosen makefile is executed with the appropriate keywords (Section
4.2.1
) which select
for specific parallel platforms (Fortran 90 compiler and MPI implementation for the specific
machine architecture). Note in many if not most cases users (administrators of these plat-
forms) will have to create their own keyword entry in the makefile due to the large variety
of (i) software needed for compilation of DL POLY 3 and (ii) ways where to install it on a
large selection of platforms. To facilitate the user with the construction of their own keyword
entry in the makefile examples are provided in the makefiles.
4. The makefile produces the executable version of the code, which as a default will be named
DLPOLY.Y and located in the execute subdirectory.
5. DL POLY also has a Java GUI. The files for this are stored in the subdirectory java. Com-
pilation of this is simple and requires running the javac compiler and the jar utility. Details
for these procedures are provided in the GUI manual [
15
].
6. To run the executable for the first time you require the files CONTROL, FIELD and CON-
FIG (and possibly TABLE if you have tabulated potentials). These must be present in the
directory from which the program is executed. (See Section
5.1
for the description of the
input files.)
7. Executing the program will produce the files OUTPUT, STATIS, REVCON and REVIVE
(and optionally HISTORY, RDFDAT and ZDNDAT) in the executing directory. (See Section
5.2
for the description of the output files.)
This simple procedure is enough to create a standard version to run most simulations. There may
however be some difficulty with array sizes. DL POLY 3 contains features which allocate arrays
after scanning the input files for a simulation. Sometimes these initial estimates are insufficient for
a long simulation when, for example, the system volume changes markedly during the simulation or
when a system is artificially constructed to have a non-uniform density. Usually, simply restarting
the program will cure the problem, but sometimes, especially when the local atom density is a way
higher than the global one, it may be necessary to amend the array sizes in accordance with the error
message obtained. A way to trigger lengthening of the density dependent global arrays the user may
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