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\chapter{\label{chapt:appendix}APPENDIX} |
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\appendix |
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\chapter{\label{chapt:oopse}Object-Oriented Parallel Simulation Engine} |
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Designing object-oriented software is hard, and designing reusable |
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object-oriented scientific software is even harder. Absence of |
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applying modern software development practices is the bottleneck of |
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Scientific Computing community\cite{Wilson2006}. For instance, in |
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the last 20 years , there are quite a few MD packages that were |
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developed to solve common MD problems and perform robust simulations |
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. However, many of the codes are legacy programs that are either |
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poorly organized or extremely complex. Usually, these packages were |
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contributed by scientists without official computer science |
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training. The development of most MD applications are lack of strong |
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coordination to enforce design and programming guidelines. Moreover, |
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most MD programs also suffer from missing design and implement |
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documents which is crucial to the maintenance and extensibility. |
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Along the way of studying structural and dynamic processes in |
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condensed phase systems like biological membranes and nanoparticles, |
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we developed and maintained an Object-Oriented Parallel Simulation |
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Engine ({\sc OOPSE}). This new molecular dynamics package has some |
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unique features |
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\begin{enumerate} |
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\item {\sc OOPSE} performs Molecular Dynamics (MD) simulations on non-standard |
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atom types (transition metals, point dipoles, sticky potentials, |
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Gay-Berne ellipsoids, or other "lumpy"atoms with orientational |
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degrees of freedom), as well as rigid bodies. |
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\item {\sc OOPSE} uses a force-based decomposition algorithm using MPI on cheap |
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Beowulf clusters to obtain very efficient parallelism. |
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\item {\sc OOPSE} integrates the equations of motion using advanced methods for |
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orientational dynamics in NVE, NVT, NPT, NPAT, and NP$\gamma$T |
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ensembles. |
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\item {\sc OOPSE} can carry out simulations on metallic systems using the |
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Embedded Atom Method (EAM) as well as the Sutton-Chen potential. |
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\item {\sc OOPSE} can perform simulations on Gay-Berne liquid crystals. |
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\item {\sc OOPSE} can simulate systems containing the extremely efficient |
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extended-Soft Sticky Dipole (SSD/E) model for water. |
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\end{enumerate} |
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|
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\section{\label{appendixSection:architecture }Architecture} |
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Mainly written by \texttt{C/C++} and \texttt{Fortran90}, {\sc OOPSE} |
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uses C++ Standard Template Library (STL) and fortran modules as the |
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foundation. As an extensive set of the STL and Fortran90 modules, |
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{\sc Base Classes} provide generic implementations of mathematical |
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objects (e.g., matrices, vectors, polynomials, random number |
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generators) and advanced data structures and algorithms(e.g., tuple, |
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bitset, generic data, string manipulation). The molecular data |
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structures for the representation of atoms, bonds, bends, torsions, |
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rigid bodies and molecules \textit{etc} are contained in the {\sc |
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Kernel} which is implemented with {\sc Base Classes} and are |
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carefully designed to provide maximum extensibility and flexibility. |
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The functionality required for applications is provide by the third |
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layer which contains Input/Output, Molecular Mechanics and Structure |
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modules. Input/Output module not only implements general methods for |
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file handling, but also defines a generic force field interface. |
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Another important component of Input/Output module is the meta-data |
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file parser, which is rewritten using ANother Tool for Language |
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Recognition(ANTLR)\cite{Parr1995, Schaps1999} syntax. The Molecular |
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Mechanics module consists of energy minimization and a wide |
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varieties of integration methods(see Chap.~\ref{chapt:methodology}). |
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The structure module contains a flexible and powerful selection |
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library which syntax is elaborated in |
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Sec.~\ref{appendixSection:syntax}. The top layer is made of the main |
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program of the package, \texttt{oopse} and it corresponding parallel |
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version \texttt{oopse\_MPI}, as well as other useful utilities, such |
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as \texttt{StatProps} (see Sec.~\ref{appendixSection:StaticProps}), |
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\texttt{DynamicProps} (see |
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Sec.~\ref{appendixSection:appendixSection:DynamicProps}), |
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\texttt{Dump2XYZ} (see |
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Sec.~\ref{appendixSection:appendixSection:Dump2XYZ}), \texttt{Hydro} |
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(see Sec.~\ref{appendixSection:appendixSection:hydrodynamics}) |
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\textit{etc}. |
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|
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\begin{figure} |
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\centering |
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\includegraphics[width=\linewidth]{architecture.eps} |
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\caption[The architecture of {\sc OOPSE}] {Overview of the structure |
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of {\sc OOPSE}} \label{appendixFig:architecture} |
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\end{figure} |
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|
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\section{\label{appendixSection:desginPattern}Design Pattern} |
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Design patterns are optimal solutions to commonly-occurring problems |
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in software design. Although originated as an architectural concept |
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for buildings and towns by Christopher Alexander |
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\cite{Alexander1987}, software patterns first became popular with |
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the wide acceptance of the book, Design Patterns: Elements of |
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Reusable Object-Oriented Software \cite{Gamma1994}. Patterns reflect |
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the experience, knowledge and insights of developers who have |
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successfully used these patterns in their own work. Patterns are |
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reusable. They provide a ready-made solution that can be adapted to |
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different problems as necessary. Pattern are expressive. they |
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provide a common vocabulary of solutions that can express large |
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solutions succinctly. |
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\subsection{\label{appendixSection:visitorPattern}Visitor Pattern} |
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Patterns are usually described using a format that includes the |
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following information: |
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\begin{enumerate} |
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\item The \emph{name} that is commonly used for the pattern. Good pattern names form a vocabulary for |
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discussing conceptual abstractions. a pattern may have more than one commonly used or recognizable name |
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in the literature. In this case it is common practice to document these nicknames or synonyms under |
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the heading of \emph{Aliases} or \emph{Also Known As}. |
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\item The \emph{motivation} or \emph{context} that this pattern applies |
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to. Sometimes, it will include some prerequisites that should be satisfied before deciding to use a pattern |
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\item The \emph{solution} to the problem that the pattern |
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addresses. It describes how to construct the necessary work products. The description may include |
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pictures, diagrams and prose which identify the pattern's structure, its participants, and their |
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collaborations, to show how the problem is solved. |
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\item The \emph{consequences} of using the given solution to solve a |
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problem, both positive and negative. |
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\end{enumerate} |
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\subsection{\label{appendixSection:templatePattern}Template Pattern} |
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As one of the latest advanced techniques emerged from |
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object-oriented community, design patterns were applied in some of |
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the modern scientific software applications, such as JMol, {\sc |
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OOPSE}\cite{Meineke05} and PROTOMOL\cite{Matthey05} \textit{etc}. |
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The following sections enumerates some of the patterns used in {\sc |
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OOPSE}. |
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\subsection{\label{appendixSection:factoryPattern}Factory Pattern} |
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\subsection{\label{appendixSection:singleton}Singleton} |
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The Singleton pattern ensures that only one instance of a class is |
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created. All objects that use an instance of that class use the same |
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instance. |
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\section{\label{appendixSection:hierarchy}Hierarchy} |
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\subsection{\label{appendixSection:factoryMethod}Factory Method} |
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The Factory Method pattern is a creational pattern which deals with |
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the problem of creating objects without specifying the exact class |
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of object that will be created. Factory Method solves this problem |
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by defining a separate method for creating the objects, which |
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subclasses can then override to specify the derived type of product |
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that will be created. |
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\section{\label{appendixSection:selectionSyntax}Selection Syntax} |
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\subsection{\label{appendixSection:visitorPattern}Visitor} |
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The purpose of the Visitor Pattern is to encapsulate an operation |
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that you want to perform on the elements of a data structure. In |
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this way, you can change the operation being performed on a |
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structure without the need of changing the classes of the elements |
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that you are operating on. |
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|
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\section{\label{appendixSection:hydrodynamics}Hydrodynamics} |
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\section{\label{appendixSection:concepts}Concepts} |
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\section{\label{appendixSection:analysisFramework}Analysis Framework} |
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OOPSE manipulates both traditional atoms as well as some objects |
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that {\it behave like atoms}. These objects can be rigid |
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collections of atoms or atoms which have orientational degrees of |
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freedom. Here is a diagram of the class heirarchy: |
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\subsection{\label{appendixSection:staticProps}Factory Properties} |
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%\begin{figure} |
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%\centering |
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%\includegraphics[width=3in]{heirarchy.eps} |
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%\caption[Class heirarchy for StuntDoubles in {\sc oopse}-3.0]{ \\ |
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%The class heirarchy of StuntDoubles in {\sc oopse}-3.0. The |
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%selection syntax allows the user to select any of the objects that |
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%are descended from a StuntDouble.} \label{oopseFig:heirarchy} |
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%\end{figure} |
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\subsection{\label{appendixSection:dynamicProps}Dynamics Properties} |
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\begin{itemize} |
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\item A {\bf StuntDouble} is {\it any} object that can be manipulated by the |
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integrators and minimizers. |
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\item An {\bf Atom} is a fundamental point-particle that can be moved around during a simulation. |
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\item A {\bf DirectionalAtom} is an atom which has {\it orientational} as well as translational degrees of freedom. |
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\item A {\bf RigidBody} is a collection of {\bf Atom}s or {\bf |
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DirectionalAtom}s which behaves as a single unit. |
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\end{itemize} |
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|
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Every Molecule, Atom and DirectionalAtom in {\sc OOPSE} have their |
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own names which are specified in the {\tt .md} file. In contrast, |
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RigidBodies are denoted by their membership and index inside a |
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particular molecule: [MoleculeName]\_RB\_[index] (the contents |
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inside the brackets depend on the specifics of the simulation). The |
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names of rigid bodies are generated automatically. For example, the |
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name of the first rigid body in a DMPC molecule is DMPC\_RB\_0. |
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|
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\section{\label{appendixSection:syntax}Syntax of the Select Command} |
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|
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The most general form of the select command is: {\tt select {\it |
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expression}}. This expression represents an arbitrary set of |
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StuntDoubles (Atoms or RigidBodies) in {\sc OOPSE}. Expressions are |
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composed of either name expressions, index expressions, predefined |
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sets, user-defined expressions, comparison operators, within |
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expressions, or logical combinations of the above expression types. |
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Expressions can be combined using parentheses and the Boolean |
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operators. |
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|
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\subsection{\label{appendixSection:logical}Logical expressions} |
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|
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The logical operators allow complex queries to be constructed out of |
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simpler ones using the standard boolean connectives {\bf and}, {\bf |
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or}, {\bf not}. Parentheses can be used to alter the precedence of |
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the operators. |
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|
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\begin{center} |
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\begin{tabular}{|ll|} |
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\hline |
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{\bf logical operator} & {\bf equivalent operator} \\ |
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\hline |
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and & ``\&'', ``\&\&'' \\ |
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or & ``$|$'', ``$||$'', ``,'' \\ |
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not & ``!'' \\ |
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\hline |
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\end{tabular} |
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\end{center} |
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|
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\subsection{\label{appendixSection:name}Name expressions} |
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|
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\begin{center} |
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\begin{tabular}{|llp{2in}|} |
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\hline {\bf type of expression} & {\bf examples} & {\bf translation |
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of |
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examples} \\ |
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\hline expression without ``.'' & select DMPC & select all |
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StuntDoubles |
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belonging to all DMPC molecules \\ |
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& select C* & select all atoms which have atom types beginning with C |
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\\ |
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& select DMPC\_RB\_* & select all RigidBodies in DMPC molecules (but |
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only select the rigid bodies, and not the atoms belonging to them). \\ |
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\hline expression has one ``.'' & select TIP3P.O\_TIP3P & select the |
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O\_TIP3P |
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atoms belonging to TIP3P molecules \\ |
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& select DMPC\_RB\_O.PO4 & select the PO4 atoms belonging to |
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the first |
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RigidBody in each DMPC molecule \\ |
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& select DMPC.20 & select the twentieth StuntDouble in each DMPC |
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molecule \\ |
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\hline expression has two ``.''s & select DMPC.DMPC\_RB\_?.* & |
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select all atoms |
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belonging to all rigid bodies within all DMPC molecules \\ |
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\hline |
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\end{tabular} |
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\end{center} |
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|
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\subsection{\label{appendixSection:index}Index expressions} |
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|
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\begin{center} |
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\begin{tabular}{|lp{4in}|} |
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\hline |
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{\bf examples} & {\bf translation of examples} \\ |
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\hline |
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select 20 & select all of the StuntDoubles belonging to Molecule 20 \\ |
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select 20 to 30 & select all of the StuntDoubles belonging to |
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molecules which have global indices between 20 (inclusive) and 30 |
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(exclusive) \\ |
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\hline |
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\end{tabular} |
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\end{center} |
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|
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\subsection{\label{appendixSection:predefined}Predefined sets} |
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|
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\begin{center} |
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\begin{tabular}{|ll|} |
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\hline |
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{\bf keyword} & {\bf description} \\ |
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\hline |
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all & select all StuntDoubles \\ |
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none & select none of the StuntDoubles \\ |
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\hline |
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\end{tabular} |
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\end{center} |
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|
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\subsection{\label{appendixSection:userdefined}User-defined expressions} |
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|
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Users can define arbitrary terms to represent groups of |
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StuntDoubles, and then use the define terms in select commands. The |
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general form for the define command is: {\bf define {\it term |
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expression}}. Once defined, the user can specify such terms in |
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boolean expressions |
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|
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{\tt define SSDWATER SSD or SSD1 or SSDRF} |
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|
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{\tt select SSDWATER} |
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|
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\subsection{\label{appendixSection:comparison}Comparison expressions} |
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|
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StuntDoubles can be selected by using comparision operators on their |
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properties. The general form for the comparison command is: a |
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property name, followed by a comparision operator and then a number. |
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|
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\begin{center} |
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\begin{tabular}{|l|l|} |
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\hline |
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{\bf property} & mass, charge \\ |
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{\bf comparison operator} & ``$>$'', ``$<$'', ``$=$'', ``$>=$'', |
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``$<=$'', ``$!=$'' \\ |
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\hline |
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\end{tabular} |
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\end{center} |
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|
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For example, the phrase {\tt select mass > 16.0 and charge < -2} |
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would select StuntDoubles which have mass greater than 16.0 and |
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charges less than -2. |
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|
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\subsection{\label{appendixSection:within}Within expressions} |
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|
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The ``within'' keyword allows the user to select all StuntDoubles |
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within the specified distance (in Angstroms) from a selection, |
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including the selected atom itself. The general form for within |
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selection is: {\tt select within(distance, expression)} |
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|
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For example, the phrase {\tt select within(2.5, PO4 or NC4)} would |
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select all StuntDoubles which are within 2.5 angstroms of PO4 or NC4 |
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atoms. |
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|
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|
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\section{\label{appendixSection:analysisFramework}Analysis Framework} |
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|
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\subsection{\label{appendixSection:StaticProps}StaticProps} |
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|
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{\tt StaticProps} can compute properties which are averaged over |
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some or all of the configurations that are contained within a dump |
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file. The most common example of a static property that can be |
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computed is the pair distribution function between atoms of type $A$ |
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and other atoms of type $B$, $g_{AB}(r)$. {\tt StaticProps} can |
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also be used to compute the density distributions of other molecules |
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in a reference frame {\it fixed to the body-fixed reference frame} |
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of a selected atom or rigid body. |
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|
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There are five seperate radial distribution functions availiable in |
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OOPSE. Since every radial distrbution function invlove the |
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calculation between pairs of bodies, {\tt -{}-sele1} and {\tt |
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-{}-sele2} must be specified to tell StaticProps which bodies to |
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include in the calculation. |
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|
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\begin{description} |
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\item[{\tt -{}-gofr}] Computes the pair distribution function, |
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\begin{equation*} |
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g_{AB}(r) = \frac{1}{\rho_B}\frac{1}{N_A} \langle \sum_{i \in A} |
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\sum_{j \in B} \delta(r - r_{ij}) \rangle |
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\end{equation*} |
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\item[{\tt -{}-r\_theta}] Computes the angle-dependent pair distribution |
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function. The angle is defined by the intermolecular vector |
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$\vec{r}$ and $z$-axis of DirectionalAtom A, |
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\begin{equation*} |
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g_{AB}(r, \cos \theta) = \frac{1}{\rho_B}\frac{1}{N_A} \langle |
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\sum_{i \in A} \sum_{j \in B} \delta(r - r_{ij}) \delta(\cos |
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\theta_{ij} - \cos \theta)\rangle |
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\end{equation*} |
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\item[{\tt -{}-r\_omega}] Computes the angle-dependent pair distribution |
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function. The angle is defined by the $z$-axes of the two |
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DirectionalAtoms A and B. |
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\begin{equation*} |
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g_{AB}(r, \cos \omega) = \frac{1}{\rho_B}\frac{1}{N_A} \langle |
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\sum_{i \in A} \sum_{j \in B} \delta(r - r_{ij}) \delta(\cos |
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\omega_{ij} - \cos \omega)\rangle |
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\end{equation*} |
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\item[{\tt -{}-theta\_omega}] Computes the pair distribution in the angular |
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space $\theta, \omega$ defined by the two angles mentioned above. |
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\begin{equation*} |
| 348 |
> |
g_{AB}(\cos\theta, \cos \omega) = \frac{1}{\rho_B}\frac{1}{N_A} |
| 349 |
> |
\langle \sum_{i \in A} \sum_{j \in B} \langle \delta(\cos |
| 350 |
> |
\theta_{ij} - \cos \theta) \delta(\cos \omega_{ij} - \cos |
| 351 |
> |
\omega)\rangle |
| 352 |
> |
\end{equation*} |
| 353 |
> |
\item[{\tt -{}-gxyz}] Calculates the density distribution of particles of type |
| 354 |
> |
B in the body frame of particle A. Therefore, {\tt -{}-originsele} |
| 355 |
> |
and {\tt -{}-refsele} must be given to define A's internal |
| 356 |
> |
coordinate set as the reference frame for the calculation. |
| 357 |
> |
\end{description} |
| 358 |
> |
|
| 359 |
> |
The vectors (and angles) associated with these angular pair |
| 360 |
> |
distribution functions are most easily seen in the figure below: |
| 361 |
> |
|
| 362 |
> |
\begin{figure} |
| 363 |
> |
\centering |
| 364 |
> |
\includegraphics[width=3in]{definition.eps} |
| 365 |
> |
\caption[Definitions of the angles between directional objects]{ \\ |
| 366 |
> |
Any two directional objects (DirectionalAtoms and RigidBodies) have |
| 367 |
> |
a set of two angles ($\theta$, and $\omega$) between the z-axes of |
| 368 |
> |
their body-fixed frames.} \label{oopseFig:gofr} |
| 369 |
> |
\end{figure} |
| 370 |
> |
|
| 371 |
> |
Due to the fact that the selected StuntDoubles from two selections |
| 372 |
> |
may be overlapped, {\tt StaticProps} performs the calculation in |
| 373 |
> |
three stages which are illustrated in |
| 374 |
> |
Fig.~\ref{oopseFig:staticPropsProcess}. |
| 375 |
> |
|
| 376 |
> |
\begin{figure} |
| 377 |
> |
\centering |
| 378 |
> |
\includegraphics[width=\linewidth]{staticPropsProcess.eps} |
| 379 |
> |
\caption[A representation of the three-stage correlations in |
| 380 |
> |
\texttt{StaticProps}]{Three-stage processing in |
| 381 |
> |
\texttt{StaticProps}. $S_1$ and $S_2$ are the numbers of selected |
| 382 |
> |
stuntdobules from {\tt -{}-sele1} and {\tt -{}-sele2} respectively, |
| 383 |
> |
while $C$ is the number of stuntdobules appearing at both sets. The |
| 384 |
> |
first stage($S_1-C$ and $S_2$) and second stages ($S_1$ and $S_2-C$) |
| 385 |
> |
are completely non-overlapping. On the contrary, the third stage($C$ |
| 386 |
> |
and $C$) are completely overlapping} |
| 387 |
> |
\label{oopseFig:staticPropsProcess} |
| 388 |
> |
\end{figure} |
| 389 |
> |
|
| 390 |
> |
The options available for {\tt StaticProps} are as follows: |
| 391 |
> |
\begin{longtable}[c]{|EFG|} |
| 392 |
> |
\caption{StaticProps Command-line Options} |
| 393 |
> |
\\ \hline |
| 394 |
> |
{\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline |
| 395 |
> |
\endhead |
| 396 |
> |
\hline |
| 397 |
> |
\endfoot |
| 398 |
> |
-h& {\tt -{}-help} & Print help and exit \\ |
| 399 |
> |
-V& {\tt -{}-version} & Print version and exit \\ |
| 400 |
> |
-i& {\tt -{}-input} & input dump file \\ |
| 401 |
> |
-o& {\tt -{}-output} & output file name \\ |
| 402 |
> |
-n& {\tt -{}-step} & process every n frame (default=`1') \\ |
| 403 |
> |
-r& {\tt -{}-nrbins} & number of bins for distance (default=`100') \\ |
| 404 |
> |
-a& {\tt -{}-nanglebins} & number of bins for cos(angle) (default= `50') \\ |
| 405 |
> |
-l& {\tt -{}-length} & maximum length (Defaults to 1/2 smallest length of first frame) \\ |
| 406 |
> |
& {\tt -{}-sele1} & select the first StuntDouble set \\ |
| 407 |
> |
& {\tt -{}-sele2} & select the second StuntDouble set \\ |
| 408 |
> |
& {\tt -{}-sele3} & select the third StuntDouble set \\ |
| 409 |
> |
& {\tt -{}-refsele} & select reference (can only be used with {\tt -{}-gxyz}) \\ |
| 410 |
> |
& {\tt -{}-molname} & molecule name \\ |
| 411 |
> |
& {\tt -{}-begin} & begin internal index \\ |
| 412 |
> |
& {\tt -{}-end} & end internal index \\ |
| 413 |
> |
\hline |
| 414 |
> |
\multicolumn{3}{|l|}{One option from the following group of options is required:} \\ |
| 415 |
> |
\hline |
| 416 |
> |
& {\tt -{}-gofr} & $g(r)$ \\ |
| 417 |
> |
& {\tt -{}-r\_theta} & $g(r, \cos(\theta))$ \\ |
| 418 |
> |
& {\tt -{}-r\_omega} & $g(r, \cos(\omega))$ \\ |
| 419 |
> |
& {\tt -{}-theta\_omega} & $g(\cos(\theta), \cos(\omega))$ \\ |
| 420 |
> |
& {\tt -{}-gxyz} & $g(x, y, z)$ \\ |
| 421 |
> |
& {\tt -{}-p2} & $P_2$ order parameter ({\tt -{}-sele1} and {\tt -{}-sele2} must be specified) \\ |
| 422 |
> |
& {\tt -{}-scd} & $S_{CD}$ order parameter(either {\tt -{}-sele1}, {\tt -{}-sele2}, {\tt -{}-sele3} are specified or {\tt -{}-molname}, {\tt -{}-begin}, {\tt -{}-end} are specified) \\ |
| 423 |
> |
& {\tt -{}-density} & density plot ({\tt -{}-sele1} must be specified) \\ |
| 424 |
> |
& {\tt -{}-slab\_density} & slab density ({\tt -{}-sele1} must be specified) |
| 425 |
> |
\end{longtable} |
| 426 |
> |
|
| 427 |
> |
\subsection{\label{appendixSection:DynamicProps}DynamicProps} |
| 428 |
> |
|
| 429 |
> |
{\tt DynamicProps} computes time correlation functions from the |
| 430 |
> |
configurations stored in a dump file. Typical examples of time |
| 431 |
> |
correlation functions are the mean square displacement and the |
| 432 |
> |
velocity autocorrelation functions. Once again, the selection |
| 433 |
> |
syntax can be used to specify the StuntDoubles that will be used for |
| 434 |
> |
the calculation. A general time correlation function can be thought |
| 435 |
> |
of as: |
| 436 |
> |
\begin{equation} |
| 437 |
> |
C_{AB}(t) = \langle \vec{u}_A(t) \cdot \vec{v}_B(0) \rangle |
| 438 |
> |
\end{equation} |
| 439 |
> |
where $\vec{u}_A(t)$ is a vector property associated with an atom of |
| 440 |
> |
type $A$ at time $t$, and $\vec{v}_B(t^{\prime})$ is a different |
| 441 |
> |
vector property associated with an atom of type $B$ at a different |
| 442 |
> |
time $t^{\prime}$. In most autocorrelation functions, the vector |
| 443 |
> |
properties ($\vec{v}$ and $\vec{u}$) and the types of atoms ($A$ and |
| 444 |
> |
$B$) are identical, and the three calculations built in to {\tt |
| 445 |
> |
DynamicProps} make these assumptions. It is possible, however, to |
| 446 |
> |
make simple modifications to the {\tt DynamicProps} code to allow |
| 447 |
> |
the use of {\it cross} time correlation functions (i.e. with |
| 448 |
> |
different vectors). The ability to use two selection scripts to |
| 449 |
> |
select different types of atoms is already present in the code. |
| 450 |
> |
|
| 451 |
> |
For large simulations, the trajectory files can sometimes reach |
| 452 |
> |
sizes in excess of several gigabytes. In order to effectively |
| 453 |
> |
analyze that amount of data. In order to prevent a situation where |
| 454 |
> |
the program runs out of memory due to large trajectories, |
| 455 |
> |
\texttt{dynamicProps} will estimate the size of free memory at |
| 456 |
> |
first, and determine the number of frames in each block, which |
| 457 |
> |
allows the operating system to load two blocks of data |
| 458 |
> |
simultaneously without swapping. Upon reading two blocks of the |
| 459 |
> |
trajectory, \texttt{dynamicProps} will calculate the time |
| 460 |
> |
correlation within the first block and the cross correlations |
| 461 |
> |
between the two blocks. This second block is then freed and then |
| 462 |
> |
incremented and the process repeated until the end of the |
| 463 |
> |
trajectory. Once the end is reached, the first block is freed then |
| 464 |
> |
incremented, until all frame pairs have been correlated in time. |
| 465 |
> |
|
| 466 |
> |
The options available for DynamicProps are as follows: |
| 467 |
> |
\begin{longtable}[c]{|EFG|} |
| 468 |
> |
\caption{DynamicProps Command-line Options} |
| 469 |
> |
\\ \hline |
| 470 |
> |
{\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline |
| 471 |
> |
\endhead |
| 472 |
> |
\hline |
| 473 |
> |
\endfoot |
| 474 |
> |
-h& {\tt -{}-help} & Print help and exit \\ |
| 475 |
> |
-V& {\tt -{}-version} & Print version and exit \\ |
| 476 |
> |
-i& {\tt -{}-input} & input dump file \\ |
| 477 |
> |
-o& {\tt -{}-output} & output file name \\ |
| 478 |
> |
& {\tt -{}-sele1} & select first StuntDouble set \\ |
| 479 |
> |
& {\tt -{}-sele2} & select second StuntDouble set (if sele2 is not set, use script from sele1) \\ |
| 480 |
> |
\hline |
| 481 |
> |
\multicolumn{3}{|l|}{One option from the following group of options is required:} \\ |
| 482 |
> |
\hline |
| 483 |
> |
-r& {\tt -{}-rcorr} & compute mean square displacement \\ |
| 484 |
> |
-v& {\tt -{}-vcorr} & compute velocity correlation function \\ |
| 485 |
> |
-d& {\tt -{}-dcorr} & compute dipole correlation function |
| 486 |
> |
\end{longtable} |
| 487 |
> |
|
| 488 |
> |
\section{\label{appendixSection:tools}Other Useful Utilities} |
| 489 |
> |
|
| 490 |
> |
\subsection{\label{appendixSection:Dump2XYZ}Dump2XYZ} |
| 491 |
> |
|
| 492 |
> |
Dump2XYZ can transform an OOPSE dump file into a xyz file which can |
| 493 |
> |
be opened by other molecular dynamics viewers such as Jmol and |
| 494 |
> |
VMD\cite{Humphrey1996}. The options available for Dump2XYZ are as |
| 495 |
> |
follows: |
| 496 |
> |
|
| 497 |
> |
|
| 498 |
> |
\begin{longtable}[c]{|EFG|} |
| 499 |
> |
\caption{Dump2XYZ Command-line Options} |
| 500 |
> |
\\ \hline |
| 501 |
> |
{\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline |
| 502 |
> |
\endhead |
| 503 |
> |
\hline |
| 504 |
> |
\endfoot |
| 505 |
> |
-h & {\tt -{}-help} & Print help and exit \\ |
| 506 |
> |
-V & {\tt -{}-version} & Print version and exit \\ |
| 507 |
> |
-i & {\tt -{}-input} & input dump file \\ |
| 508 |
> |
-o & {\tt -{}-output} & output file name \\ |
| 509 |
> |
-n & {\tt -{}-frame} & print every n frame (default=`1') \\ |
| 510 |
> |
-w & {\tt -{}-water} & skip the the waters (default=off) \\ |
| 511 |
> |
-m & {\tt -{}-periodicBox} & map to the periodic box (default=off)\\ |
| 512 |
> |
-z & {\tt -{}-zconstraint} & replace the atom types of zconstraint molecules (default=off) \\ |
| 513 |
> |
-r & {\tt -{}-rigidbody} & add a pseudo COM atom to rigidbody (default=off) \\ |
| 514 |
> |
-t & {\tt -{}-watertype} & replace the atom type of water model (default=on) \\ |
| 515 |
> |
-b & {\tt -{}-basetype} & using base atom type (default=off) \\ |
| 516 |
> |
& {\tt -{}-repeatX} & The number of images to repeat in the x direction (default=`0') \\ |
| 517 |
> |
& {\tt -{}-repeatY} & The number of images to repeat in the y direction (default=`0') \\ |
| 518 |
> |
& {\tt -{}-repeatZ} & The number of images to repeat in the z direction (default=`0') \\ |
| 519 |
> |
-s & {\tt -{}-selection} & By specifying {\tt -{}-selection}=``selection command'' with Dump2XYZ, the user can select an arbitrary set of StuntDoubles to be |
| 520 |
> |
converted. \\ |
| 521 |
> |
& {\tt -{}-originsele} & By specifying {\tt -{}-originsele}=``selection command'' with Dump2XYZ, the user can re-center the origin of the system around a specific StuntDouble \\ |
| 522 |
> |
& {\tt -{}-refsele} & In order to rotate the system, {\tt -{}-originsele} and {\tt -{}-refsele} must be given to define the new coordinate set. A StuntDouble which contains a dipole (the direction of the dipole is always (0, 0, 1) in body frame) is specified by {\tt -{}-originsele}. The new x-z plane is defined by the direction of the dipole and the StuntDouble is specified by {\tt -{}-refsele}. |
| 523 |
> |
\end{longtable} |
| 524 |
> |
|
| 525 |
> |
\subsection{\label{appendixSection:hydrodynamics}Hydro} |
| 526 |
> |
The options available for Hydro are as follows: |
| 527 |
> |
\begin{longtable}[c]{|EFG|} |
| 528 |
> |
\caption{Hydrodynamics Command-line Options} |
| 529 |
> |
\\ \hline |
| 530 |
> |
{\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline |
| 531 |
> |
\endhead |
| 532 |
> |
\hline |
| 533 |
> |
\endfoot |
| 534 |
> |
-h & {\tt -{}-help} & Print help and exit \\ |
| 535 |
> |
-V & {\tt -{}-version} & Print version and exit \\ |
| 536 |
> |
-i & {\tt -{}-input} & input dump file \\ |
| 537 |
> |
-o & {\tt -{}-output} & output file prefix (default=`hydro') \\ |
| 538 |
> |
-b & {\tt -{}-beads} & generate the beads only, hydrodynamics calculation will not be performed (default=off)\\ |
| 539 |
> |
& {\tt -{}-model} & hydrodynamics model (supports ``AnalyticalModel'', ``RoughShell'' and ``BeadModel'') \\ |
| 540 |
> |
\end{longtable} |
