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1 < \chapter{\label{chapt:appendix}APPENDIX}
1 > \appendix
2 > \chapter{\label{chapt:oopse}Object-Oriented Parallel Simulation Engine}
3  
4   Designing object-oriented software is hard, and designing reusable
5   object-oriented scientific software is even harder. Absence of
6   applying modern software development practices is the bottleneck of
7 < Scientific Computing community\cite{wilson}. For instance, in the
8 < last 20 years , there are quite a few MD packages that were
7 > Scientific Computing community\cite{Wilson2006}. For instance, in
8 > the last 20 years , there are quite a few MD packages that were
9   developed to solve common MD problems and perform robust simulations
10   . However, many of the codes are legacy programs that are either
11   poorly organized or extremely complex. Usually, these packages were
# Line 13 | Line 14 | documents which is crucial to the maintenance and exte
14   coordination to enforce design and programming guidelines. Moreover,
15   most MD programs also suffer from missing design and implement
16   documents which is crucial to the maintenance and extensibility.
17 + Along the way of studying structural and dynamic processes in
18 + condensed phase systems like biological membranes and nanoparticles,
19 + we developed and maintained an Object-Oriented Parallel Simulation
20 + Engine ({\sc OOPSE}). This new molecular dynamics package has some
21 + unique features
22 + \begin{enumerate}
23 +  \item {\sc OOPSE} performs Molecular Dynamics (MD) simulations on non-standard
24 + atom types (transition metals, point dipoles, sticky potentials,
25 + Gay-Berne ellipsoids, or other "lumpy"atoms with orientational
26 + degrees of freedom), as well as rigid bodies.
27 +  \item {\sc OOPSE} uses a force-based decomposition algorithm using MPI on cheap
28 + Beowulf clusters to obtain very efficient parallelism.
29 +  \item {\sc OOPSE} integrates the equations of motion using advanced methods for
30 + orientational dynamics in NVE, NVT, NPT, NPAT, and NP$\gamma$T
31 + ensembles.
32 +  \item {\sc OOPSE} can carry out simulations on metallic systems using the
33 + Embedded Atom Method (EAM) as well as the Sutton-Chen potential.
34 +  \item {\sc OOPSE} can perform simulations on Gay-Berne liquid crystals.
35 +  \item  {\sc OOPSE} can simulate systems containing the extremely efficient
36 + extended-Soft Sticky Dipole (SSD/E) model for water.
37 + \end{enumerate}
38  
39 + \section{\label{appendixSection:architecture }Architecture}
40 +
41 + Mainly written by \texttt{C/C++} and \texttt{Fortran90}, {\sc OOPSE}
42 + uses C++ Standard Template Library (STL) and fortran modules as the
43 + foundation. As an extensive set of the STL and Fortran90 modules,
44 + {\sc Base Classes} provide generic implementations of mathematical
45 + objects (e.g., matrices, vectors, polynomials, random number
46 + generators) and advanced data structures and algorithms(e.g., tuple,
47 + bitset, generic data, string manipulation). The molecular data
48 + structures for the representation of atoms, bonds, bends, torsions,
49 + rigid bodies and molecules \textit{etc} are contained in the {\sc
50 + Kernel} which is implemented with {\sc Base Classes} and are
51 + carefully designed to provide maximum extensibility and flexibility.
52 + The functionality required for applications is provide by the third
53 + layer which contains Input/Output, Molecular Mechanics and Structure
54 + modules. Input/Output module not only implements general methods for
55 + file handling, but also defines a generic force field interface.
56 + Another important component of Input/Output module is the meta-data
57 + file parser, which is rewritten using ANother Tool for Language
58 + Recognition(ANTLR)\cite{Parr1995, Schaps1999} syntax. The Molecular
59 + Mechanics module consists of energy minimization and a wide
60 + varieties of integration methods(see Chap.~\ref{chapt:methodology}).
61 + The structure module contains a flexible and powerful selection
62 + library which syntax is elaborated in
63 + Sec.~\ref{appendixSection:syntax}. The top layer is made of the main
64 + program of the package, \texttt{oopse} and it corresponding parallel
65 + version \texttt{oopse\_MPI}, as well as other useful utilities, such
66 + as \texttt{StatProps} (see Sec.~\ref{appendixSection:StaticProps}),
67 + \texttt{DynamicProps} (see
68 + Sec.~\ref{appendixSection:appendixSection:DynamicProps}),
69 + \texttt{Dump2XYZ} (see
70 + Sec.~\ref{appendixSection:appendixSection:Dump2XYZ}), \texttt{Hydro}
71 + (see Sec.~\ref{appendixSection:appendixSection:hydrodynamics})
72 + \textit{etc}.
73 +
74 + \begin{figure}
75 + \centering
76 + \includegraphics[width=\linewidth]{architecture.eps}
77 + \caption[The architecture of {\sc OOPSE}] {Overview of the structure
78 + of {\sc OOPSE}} \label{appendixFig:architecture}
79 + \end{figure}
80 +
81   \section{\label{appendixSection:desginPattern}Design Pattern}
82  
83   Design patterns are optimal solutions to commonly-occurring problems
84   in software design. Although originated as an architectural concept
85 < for buildings and towns by Christopher Alexander \cite{alexander},
86 < software patterns first became popular with the wide acceptance of
87 < the book, Design Patterns: Elements of Reusable Object-Oriented
88 < Software \cite{gamma94}. Patterns reflect the experience, knowledge
89 < and insights of developers who have successfully used these patterns
90 < in their own work. Patterns are reusable. They provide a ready-made
91 < solution that can be adapted to different problems as necessary.
92 < Pattern are expressive. they provide a common vocabulary of
93 < solutions that can express large solutions succinctly.
85 > for buildings and towns by Christopher Alexander
86 > \cite{Alexander1987}, software patterns first became popular with
87 > the wide acceptance of the book, Design Patterns: Elements of
88 > Reusable Object-Oriented Software \cite{Gamma1994}. Patterns reflect
89 > the experience, knowledge and insights of developers who have
90 > successfully used these patterns in their own work. Patterns are
91 > reusable. They provide a ready-made solution that can be adapted to
92 > different problems as necessary. Pattern are expressive. they
93 > provide a common vocabulary of solutions that can express large
94 > solutions succinctly.
95  
96   Patterns are usually described using a format that includes the
97   following information:
# Line 47 | Line 112 | the modern scientific software applications, such as J
112  
113   As one of the latest advanced techniques emerged from
114   object-oriented community, design patterns were applied in some of
115 < the modern scientific software applications, such as JMol, OOPSE
116 < \cite{Meineke05} and PROTOMOL \cite{Matthey05} \textit{etc}.
115 > the modern scientific software applications, such as JMol, {\sc
116 > OOPSE}\cite{Meineke05} and PROTOMOL\cite{Matthey05} \textit{etc}.
117 > The following sections enumerates some of the patterns used in {\sc
118 > OOPSE}.
119  
120   \subsection{\label{appendixSection:singleton}Singleton}
121 < The Singleton pattern ensures that only one instance of a class is
122 < created. All objects that use an instance of that class use the same
123 < instance.
121 > The Singleton pattern not only provides a mechanism to restrict
122 > instantiation of a class to one object, but also provides a global
123 > point of access to the object. Currently implemented as a global
124 > variable, the logging utility which reports error and warning
125 > messages to the console in {\sc OOPSE} is a good candidate for
126 > applying the Singleton pattern to avoid the global namespace
127 > pollution.Although the singleton pattern can be implemented in
128 > various ways  to account for different aspects of the software
129 > designs, such as lifespan control \textit{etc}, we only use the
130 > static data approach in {\sc OOPSE}. {\tt IntegratorFactory} class
131 > is declared as
132 > \begin{lstlisting}[float,caption={[A classic Singleton design pattern implementation(I)] Declaration of {\tt IntegratorFactory} class.},label={appendixScheme:singletonDeclaration}]
133  
134 + class IntegratorFactory {
135 +  public:
136 +    static IntegratorFactory* getInstance();
137 +    protected:
138 +      IntegratorFactory();
139 +    private:
140 +      static IntegratorFactory* instance_;
141 + };
142 +
143 + \end{lstlisting}
144 + The corresponding implementation is
145 + \begin{lstlisting}[float,caption={[A classic implementation of Singleton design pattern (II)] Implementation of {\tt IntegratorFactory} class.},label={appendixScheme:singletonImplementation}]
146 +
147 + IntegratorFactory::instance_ = NULL;
148 +
149 + IntegratorFactory* getInstance() {
150 +  if (instance_ == NULL){
151 +    instance_ = new IntegratorFactory;
152 +  }
153 +  return instance_;
154 + }
155 +
156 + \end{lstlisting}
157 + Since constructor is declared as {\tt protected}, a client can not
158 + instantiate {\tt IntegratorFactory} directly. Moreover, since the
159 + member function {\tt getInstance} serves as the only entry of access
160 + to {\tt IntegratorFactory}, this approach fulfills the basic
161 + requirement, a single instance. Another consequence of this approach
162 + is the automatic destruction since static data are destroyed upon
163 + program termination.
164 +
165   \subsection{\label{appendixSection:factoryMethod}Factory Method}
59 The Factory Method pattern is a creational pattern which deals with
60 the problem of creating objects without specifying the exact class
61 of object that will be created. Factory Method solves this problem
62 by defining a separate method for creating the objects, which
63 subclasses can then override to specify the derived type of product
64 that will be created.
166  
167 + Categoried as a creational pattern, the Factory Method pattern deals
168 + with the problem of creating objects without specifying the exact
169 + class of object that will be created. Factory Method is typically
170 + implemented by delegating the creation operation to the subclasses.
171  
172 + Registers a creator with a type identifier. Looks up the type
173 + identifier in the internal map. If it is found, it invokes the
174 + corresponding creator for the type identifier and returns its
175 + result.
176 + \begin{lstlisting}[float,caption={[The implementation of Factory pattern (I)].},label={appendixScheme:factoryDeclaration}]
177 +
178 + class IntegratorFactory {
179 +  public:
180 +    typedef std::map<string, IntegratorCreator*> CreatorMapType;
181 +
182 +    bool registerIntegrator(IntegratorCreator* creator) {
183 +      return creatorMap_.insert(creator->getIdent(), creator).second;
184 +    }
185 +
186 +    Integrator* createIntegrator(const string& id, SimInfo* info) {
187 +      Integrator* result = NULL;
188 +      CreatorMapType::iterator i = creatorMap_.find(id);
189 +      if (i != creatorMap_.end()) {
190 +        result = (i->second)->create(info);
191 +      }
192 +      return result;
193 +    }
194 +
195 +  private:
196 +    CreatorMapType creatorMap_;
197 + };
198 + \end{lstlisting}
199 + \begin{lstlisting}[float,caption={[The implementation of Factory pattern (III)]Souce code of creator classes.},label={appendixScheme:integratorCreator}]
200 +
201 + class IntegratorCreator {
202 +  public:
203 +    IntegratorCreator(const string& ident) : ident_(ident) {}
204 +
205 +    const string& getIdent() const { return ident_; }
206 +
207 +    virtual Integrator* create(SimInfo* info) const = 0;
208 +
209 +  private:
210 +    string ident_;
211 + };
212 +
213 + template<class ConcreteIntegrator>
214 + class IntegratorBuilder : public IntegratorCreator {
215 +  public:
216 +    IntegratorBuilder(const string& ident) : IntegratorCreator(ident) {}
217 +    virtual  Integrator* create(SimInfo* info) const {
218 +      return new ConcreteIntegrator(info);
219 +    }
220 + };
221 + \end{lstlisting}
222 +
223   \subsection{\label{appendixSection:visitorPattern}Visitor}
224 +
225   The purpose of the Visitor Pattern is to encapsulate an operation
226 < that you want to perform on the elements of a data structure. In
227 < this way, you can change the operation being performed on a
228 < structure without the need of changing the classes of the elements
229 < that you are operating on.
226 > that you want to perform on the elements. The operation being
227 > performed on a structure can be switched without changing the
228 > interfaces  of the elements. In other words, one can add virtual
229 > functions into a set of classes without modifying their interfaces.
230 > The UML class diagram of Visitor patten is shown in
231 > Fig.~\ref{appendixFig:visitorUML}. {\tt Dump2XYZ} program in
232 > Sec.~\ref{appendixSection:Dump2XYZ} uses Visitor pattern
233 > extensively.
234  
235 + \begin{figure}
236 + \centering
237 + \includegraphics[width=\linewidth]{visitor.eps}
238 + \caption[The architecture of {\sc OOPSE}] {Overview of the structure
239 + of {\sc OOPSE}} \label{appendixFig:visitorUML}
240 + \end{figure}
241  
242 < \subsection{\label{appendixSection:templateMethod}Template Method}
242 > \begin{lstlisting}[float,caption={[The implementation of Visitor pattern (I)]Source code of the visitor classes.},label={appendixScheme:visitor}]
243  
244 < \section{\label{appendixSection:analysisFramework}Analysis Framework}
244 > class BaseVisitor{
245 >  public:
246 >    virtual void visit(Atom* atom);
247 >    virtual void visit(DirectionalAtom* datom);
248 >    virtual void visit(RigidBody* rb);
249 > };
250  
251 < \section{\label{appendixSection:hierarchy}Hierarchy}
251 > \end{lstlisting}
252  
253 < \subsection{\label{appendixSection:selectionSyntax}Selection Syntax}
253 > \begin{lstlisting}[float,caption={[The implementation of Visitor pattern (II)]Source code of the element classes.},label={appendixScheme:element}]
254  
255 < \subsection{\label{appendixSection:hydrodynamics}Hydrodynamics}
255 > class StuntDouble {
256 >  public:
257 >    virtual void accept(BaseVisitor* v) = 0;
258 > };
259  
260 < \subsection{\label{appendixSection:staticProps}Static Properties}
260 > class Atom: public StuntDouble {
261 >  public:
262 >    virtual void accept{BaseVisitor* v*} {
263 >      v->visit(this);
264 >    }
265 > };
266  
267 < \subsection{\label{appendixSection:dynamicProps}Dynamics Properties}
267 > class DirectionalAtom: public Atom {
268 >  public:
269 >    virtual void accept{BaseVisitor* v*} {
270 >      v->visit(this);
271 >    }
272 > };
273 >
274 > class RigidBody: public StuntDouble {
275 >  public:
276 >    virtual void accept{BaseVisitor* v*} {
277 >      v->visit(this);
278 >    }
279 > };
280 >
281 > \end{lstlisting}
282 >
283 > \section{\label{appendixSection:concepts}Concepts}
284 >
285 > OOPSE manipulates both traditional atoms as well as some objects
286 > that {\it behave like atoms}.  These objects can be rigid
287 > collections of atoms or atoms which have orientational degrees of
288 > freedom.  A diagram of the class heirarchy is illustrated in
289 > Fig.~\ref{oopseFig:heirarchy}. Every Molecule, Atom and
290 > DirectionalAtom in {\sc OOPSE} have their own names which are
291 > specified in the {\tt .md} file. In contrast, RigidBodies are
292 > denoted by their membership and index inside a particular molecule:
293 > [MoleculeName]\_RB\_[index] (the contents inside the brackets depend
294 > on the specifics of the simulation). The names of rigid bodies are
295 > generated automatically. For example, the name of the first rigid
296 > body in a DMPC molecule is DMPC\_RB\_0.
297 > \begin{figure}
298 > \centering
299 > \includegraphics[width=\linewidth]{heirarchy.eps}
300 > \caption[Class heirarchy for ojects in {\sc OOPSE}]{ A diagram of
301 > the class heirarchy.
302 > \begin{itemize}
303 > \item A {\bf StuntDouble} is {\it any} object that can be manipulated by the
304 > integrators and minimizers.
305 > \item An {\bf Atom} is a fundamental point-particle that can be moved around during a simulation.
306 > \item A {\bf DirectionalAtom} is an atom which has {\it orientational} as well as translational degrees of freedom.
307 > \item A {\bf RigidBody} is a collection of {\bf Atom}s or {\bf
308 > DirectionalAtom}s which behaves as a single unit.
309 > \end{itemize}
310 > } \label{oopseFig:heirarchy}
311 > \end{figure}
312 >
313 > \section{\label{appendixSection:syntax}Syntax of the Select Command}
314 >
315 > The most general form of the select command is: {\tt select {\it
316 > expression}}. This expression represents an arbitrary set of
317 > StuntDoubles (Atoms or RigidBodies) in {\sc OOPSE}. Expressions are
318 > composed of either name expressions, index expressions, predefined
319 > sets, user-defined expressions, comparison operators, within
320 > expressions, or logical combinations of the above expression types.
321 > Expressions can be combined using parentheses and the Boolean
322 > operators.
323 >
324 > \subsection{\label{appendixSection:logical}Logical expressions}
325 >
326 > The logical operators allow complex queries to be constructed out of
327 > simpler ones using the standard boolean connectives {\bf and}, {\bf
328 > or}, {\bf not}. Parentheses can be used to alter the precedence of
329 > the operators.
330 >
331 > \begin{center}
332 > \begin{tabular}{|ll|}
333 > \hline
334 > {\bf logical operator} & {\bf equivalent operator}  \\
335 > \hline
336 > and & ``\&'', ``\&\&'' \\
337 > or & ``$|$'', ``$||$'', ``,'' \\
338 > not & ``!''  \\
339 > \hline
340 > \end{tabular}
341 > \end{center}
342 >
343 > \subsection{\label{appendixSection:name}Name expressions}
344 >
345 > \begin{center}
346 > \begin{tabular}{|llp{2in}|}
347 > \hline {\bf type of expression} & {\bf examples} & {\bf translation
348 > of
349 > examples} \\
350 > \hline expression without ``.'' & select DMPC & select all
351 > StuntDoubles
352 > belonging to all DMPC molecules \\
353 > & select C* & select all atoms which have atom types beginning with C
354 > \\
355 > & select DMPC\_RB\_* & select all RigidBodies in DMPC molecules (but
356 > only select the rigid bodies, and not the atoms belonging to them). \\
357 > \hline expression has one ``.'' & select TIP3P.O\_TIP3P & select the
358 > O\_TIP3P
359 > atoms belonging to TIP3P molecules \\
360 > & select DMPC\_RB\_O.PO4 & select the PO4 atoms belonging to
361 > the first
362 > RigidBody in each DMPC molecule \\
363 > & select DMPC.20 & select the twentieth StuntDouble in each DMPC
364 > molecule \\
365 > \hline expression has two ``.''s & select DMPC.DMPC\_RB\_?.* &
366 > select all atoms
367 > belonging to all rigid bodies within all DMPC molecules \\
368 > \hline
369 > \end{tabular}
370 > \end{center}
371 >
372 > \subsection{\label{appendixSection:index}Index expressions}
373 >
374 > \begin{center}
375 > \begin{tabular}{|lp{4in}|}
376 > \hline
377 > {\bf examples} & {\bf translation of examples} \\
378 > \hline
379 > select 20 & select all of the StuntDoubles belonging to Molecule 20 \\
380 > select 20 to 30 & select all of the StuntDoubles belonging to
381 > molecules which have global indices between 20 (inclusive) and 30
382 > (exclusive) \\
383 > \hline
384 > \end{tabular}
385 > \end{center}
386 >
387 > \subsection{\label{appendixSection:predefined}Predefined sets}
388 >
389 > \begin{center}
390 > \begin{tabular}{|ll|}
391 > \hline
392 > {\bf keyword} & {\bf description} \\
393 > \hline
394 > all & select all StuntDoubles \\
395 > none & select none of the StuntDoubles \\
396 > \hline
397 > \end{tabular}
398 > \end{center}
399 >
400 > \subsection{\label{appendixSection:userdefined}User-defined expressions}
401 >
402 > Users can define arbitrary terms to represent groups of
403 > StuntDoubles, and then use the define terms in select commands. The
404 > general form for the define command is: {\bf define {\it term
405 > expression}}. Once defined, the user can specify such terms in
406 > boolean expressions
407 >
408 > {\tt define SSDWATER SSD or SSD1 or SSDRF}
409 >
410 > {\tt select SSDWATER}
411 >
412 > \subsection{\label{appendixSection:comparison}Comparison expressions}
413 >
414 > StuntDoubles can be selected by using comparision operators on their
415 > properties. The general form for the comparison command is: a
416 > property name, followed by a comparision operator and then a number.
417 >
418 > \begin{center}
419 > \begin{tabular}{|l|l|}
420 > \hline
421 > {\bf property} & mass, charge \\
422 > {\bf comparison operator} & ``$>$'', ``$<$'', ``$=$'', ``$>=$'',
423 > ``$<=$'', ``$!=$'' \\
424 > \hline
425 > \end{tabular}
426 > \end{center}
427 >
428 > For example, the phrase {\tt select mass > 16.0 and charge < -2}
429 > would select StuntDoubles which have mass greater than 16.0 and
430 > charges less than -2.
431 >
432 > \subsection{\label{appendixSection:within}Within expressions}
433 >
434 > The ``within'' keyword allows the user to select all StuntDoubles
435 > within the specified distance (in Angstroms) from a selection,
436 > including the selected atom itself. The general form for within
437 > selection is: {\tt select within(distance, expression)}
438 >
439 > For example, the phrase {\tt select within(2.5, PO4 or NC4)} would
440 > select all StuntDoubles which are within 2.5 angstroms of PO4 or NC4
441 > atoms.
442 >
443 >
444 > \section{\label{appendixSection:analysisFramework}Analysis Framework}
445 >
446 > \subsection{\label{appendixSection:StaticProps}StaticProps}
447 >
448 > {\tt StaticProps} can compute properties which are averaged over
449 > some or all of the configurations that are contained within a dump
450 > file. The most common example of a static property that can be
451 > computed is the pair distribution function between atoms of type $A$
452 > and other atoms of type $B$, $g_{AB}(r)$.  {\tt StaticProps} can
453 > also be used to compute the density distributions of other molecules
454 > in a reference frame {\it fixed to the body-fixed reference frame}
455 > of a selected atom or rigid body.
456 >
457 > There are five seperate radial distribution functions availiable in
458 > OOPSE. Since every radial distrbution function invlove the
459 > calculation between pairs of bodies, {\tt -{}-sele1} and {\tt
460 > -{}-sele2} must be specified to tell StaticProps which bodies to
461 > include in the calculation.
462 >
463 > \begin{description}
464 > \item[{\tt -{}-gofr}] Computes the pair distribution function,
465 > \begin{equation*}
466 > g_{AB}(r) = \frac{1}{\rho_B}\frac{1}{N_A} \langle \sum_{i \in A}
467 > \sum_{j \in B} \delta(r - r_{ij}) \rangle
468 > \end{equation*}
469 > \item[{\tt -{}-r\_theta}] Computes the angle-dependent pair distribution
470 > function. The angle is defined by the intermolecular vector
471 > $\vec{r}$ and $z$-axis of DirectionalAtom A,
472 > \begin{equation*}
473 > g_{AB}(r, \cos \theta) = \frac{1}{\rho_B}\frac{1}{N_A} \langle
474 > \sum_{i \in A} \sum_{j \in B} \delta(r - r_{ij}) \delta(\cos
475 > \theta_{ij} - \cos \theta)\rangle
476 > \end{equation*}
477 > \item[{\tt -{}-r\_omega}] Computes the angle-dependent pair distribution
478 > function. The angle is defined by the $z$-axes of the two
479 > DirectionalAtoms A and B.
480 > \begin{equation*}
481 > g_{AB}(r, \cos \omega) = \frac{1}{\rho_B}\frac{1}{N_A} \langle
482 > \sum_{i \in A} \sum_{j \in B} \delta(r - r_{ij}) \delta(\cos
483 > \omega_{ij} - \cos \omega)\rangle
484 > \end{equation*}
485 > \item[{\tt -{}-theta\_omega}] Computes the pair distribution in the angular
486 > space $\theta, \omega$ defined by the two angles mentioned above.
487 > \begin{equation*}
488 > g_{AB}(\cos\theta, \cos \omega) = \frac{1}{\rho_B}\frac{1}{N_A}
489 > \langle \sum_{i \in A} \sum_{j \in B} \langle \delta(\cos
490 > \theta_{ij} - \cos \theta) \delta(\cos \omega_{ij} - \cos
491 > \omega)\rangle
492 > \end{equation*}
493 > \item[{\tt -{}-gxyz}] Calculates the density distribution of particles of type
494 > B in the body frame of particle A. Therefore, {\tt -{}-originsele}
495 > and {\tt -{}-refsele} must be given to define A's internal
496 > coordinate set as the reference frame for the calculation.
497 > \end{description}
498 >
499 > The vectors (and angles) associated with these angular pair
500 > distribution functions are most easily seen in the figure below:
501 >
502 > \begin{figure}
503 > \centering
504 > \includegraphics[width=3in]{definition.eps}
505 > \caption[Definitions of the angles between directional objects]{ \\
506 > Any two directional objects (DirectionalAtoms and RigidBodies) have
507 > a set of two angles ($\theta$, and $\omega$) between the z-axes of
508 > their body-fixed frames.} \label{oopseFig:gofr}
509 > \end{figure}
510 >
511 > Due to the fact that the selected StuntDoubles from two selections
512 > may be overlapped, {\tt StaticProps} performs the calculation in
513 > three stages which are illustrated in
514 > Fig.~\ref{oopseFig:staticPropsProcess}.
515 >
516 > \begin{figure}
517 > \centering
518 > \includegraphics[width=\linewidth]{staticPropsProcess.eps}
519 > \caption[A representation of the three-stage correlations in
520 > \texttt{StaticProps}]{This diagram illustrates three-stage
521 > processing used by \texttt{StaticProps}. $S_1$ and $S_2$ are the
522 > numbers of selected stuntdobules from {\tt -{}-sele1} and {\tt
523 > -{}-sele2} respectively, while $C$ is the number of stuntdobules
524 > appearing at both sets. The first stage($S_1-C$ and $S_2$) and
525 > second stages ($S_1$ and $S_2-C$) are completely non-overlapping. On
526 > the contrary, the third stage($C$ and $C$) are completely
527 > overlapping} \label{oopseFig:staticPropsProcess}
528 > \end{figure}
529 >
530 > The options available for {\tt StaticProps} are as follows:
531 > \begin{longtable}[c]{|EFG|}
532 > \caption{StaticProps Command-line Options}
533 > \\ \hline
534 > {\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline
535 > \endhead
536 > \hline
537 > \endfoot
538 >  -h& {\tt -{}-help}                    &  Print help and exit \\
539 >  -V& {\tt -{}-version}                 &  Print version and exit \\
540 >  -i& {\tt -{}-input}          &  input dump file \\
541 >  -o& {\tt -{}-output}         &  output file name \\
542 >  -n& {\tt -{}-step}                &  process every n frame  (default=`1') \\
543 >  -r& {\tt -{}-nrbins}              &  number of bins for distance  (default=`100') \\
544 >  -a& {\tt -{}-nanglebins}          &  number of bins for cos(angle)  (default= `50') \\
545 >  -l& {\tt -{}-length}           &  maximum length (Defaults to 1/2 smallest length of first frame) \\
546 >    & {\tt -{}-sele1}   & select the first StuntDouble set \\
547 >    & {\tt -{}-sele2}   & select the second StuntDouble set \\
548 >    & {\tt -{}-sele3}   & select the third StuntDouble set \\
549 >    & {\tt -{}-refsele} & select reference (can only be used with {\tt -{}-gxyz}) \\
550 >    & {\tt -{}-molname}           & molecule name \\
551 >    & {\tt -{}-begin}                & begin internal index \\
552 >    & {\tt -{}-end}                  & end internal index \\
553 > \hline
554 > \multicolumn{3}{|l|}{One option from the following group of options is required:} \\
555 > \hline
556 >    &  {\tt -{}-gofr}                    &  $g(r)$ \\
557 >    &  {\tt -{}-r\_theta}                 &  $g(r, \cos(\theta))$ \\
558 >    &  {\tt -{}-r\_omega}                 &  $g(r, \cos(\omega))$ \\
559 >    &  {\tt -{}-theta\_omega}             &  $g(\cos(\theta), \cos(\omega))$ \\
560 >    &  {\tt -{}-gxyz}                    &  $g(x, y, z)$ \\
561 >    &  {\tt -{}-p2}                      &  $P_2$ order parameter ({\tt -{}-sele1} and {\tt -{}-sele2} must be specified) \\
562 >    &  {\tt -{}-scd}                     &  $S_{CD}$ order parameter(either {\tt -{}-sele1}, {\tt -{}-sele2}, {\tt -{}-sele3} are specified or {\tt -{}-molname}, {\tt -{}-begin}, {\tt -{}-end} are specified) \\
563 >    &  {\tt -{}-density}                 &  density plot ({\tt -{}-sele1} must be specified) \\
564 >    &  {\tt -{}-slab\_density}           &  slab density ({\tt -{}-sele1} must be specified)
565 > \end{longtable}
566 >
567 > \subsection{\label{appendixSection:DynamicProps}DynamicProps}
568 >
569 > {\tt DynamicProps} computes time correlation functions from the
570 > configurations stored in a dump file.  Typical examples of time
571 > correlation functions are the mean square displacement and the
572 > velocity autocorrelation functions.   Once again, the selection
573 > syntax can be used to specify the StuntDoubles that will be used for
574 > the calculation.  A general time correlation function can be thought
575 > of as:
576 > \begin{equation}
577 > C_{AB}(t) = \langle \vec{u}_A(t) \cdot \vec{v}_B(0) \rangle
578 > \end{equation}
579 > where $\vec{u}_A(t)$ is a vector property associated with an atom of
580 > type $A$ at time $t$, and $\vec{v}_B(t^{\prime})$ is a different
581 > vector property associated with an atom of type $B$ at a different
582 > time $t^{\prime}$.  In most autocorrelation functions, the vector
583 > properties ($\vec{v}$ and $\vec{u}$) and the types of atoms ($A$ and
584 > $B$) are identical, and the three calculations built in to {\tt
585 > DynamicProps} make these assumptions.  It is possible, however, to
586 > make simple modifications to the {\tt DynamicProps} code to allow
587 > the use of {\it cross} time correlation functions (i.e. with
588 > different vectors).  The ability to use two selection scripts to
589 > select different types of atoms is already present in the code.
590 >
591 > For large simulations, the trajectory files can sometimes reach
592 > sizes in excess of several gigabytes. In order to effectively
593 > analyze that amount of data. In order to prevent a situation where
594 > the program runs out of memory due to large trajectories,
595 > \texttt{dynamicProps} will estimate the size of free memory at
596 > first, and determine the number of frames in each block, which
597 > allows the operating system to load two blocks of data
598 > simultaneously without swapping. Upon reading two blocks of the
599 > trajectory, \texttt{dynamicProps} will calculate the time
600 > correlation within the first block and the cross correlations
601 > between the two blocks. This second block is then freed and then
602 > incremented and the process repeated until the end of the
603 > trajectory. Once the end is reached, the first block is freed then
604 > incremented, until all frame pairs have been correlated in time.
605 > This process is illustrated in
606 > Fig.~\ref{oopseFig:dynamicPropsProcess}.
607 >
608 > \begin{figure}
609 > \centering
610 > \includegraphics[width=\linewidth]{dynamicPropsProcess.eps}
611 > \caption[A representation of the block correlations in
612 > \texttt{dynamicProps}]{This diagram illustrates block correlations
613 > processing in \texttt{dynamicProps}. The shaded region represents
614 > the self correlation of the block, and the open blocks are read one
615 > at a time and the cross correlations between blocks are calculated.}
616 > \label{oopseFig:dynamicPropsProcess}
617 > \end{figure}
618 >
619 > The options available for DynamicProps are as follows:
620 > \begin{longtable}[c]{|EFG|}
621 > \caption{DynamicProps Command-line Options}
622 > \\ \hline
623 > {\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline
624 > \endhead
625 > \hline
626 > \endfoot
627 >  -h& {\tt -{}-help}                   & Print help and exit \\
628 >  -V& {\tt -{}-version}                & Print version and exit \\
629 >  -i& {\tt -{}-input}         & input dump file \\
630 >  -o& {\tt -{}-output}        & output file name \\
631 >    & {\tt -{}-sele1} & select first StuntDouble set \\
632 >    & {\tt -{}-sele2} & select second StuntDouble set (if sele2 is not set, use script from sele1) \\
633 > \hline
634 > \multicolumn{3}{|l|}{One option from the following group of options is required:} \\
635 > \hline
636 >  -r& {\tt -{}-rcorr}                  & compute mean square displacement \\
637 >  -v& {\tt -{}-vcorr}                  & compute velocity correlation function \\
638 >  -d& {\tt -{}-dcorr}                  & compute dipole correlation function
639 > \end{longtable}
640 >
641 > \section{\label{appendixSection:tools}Other Useful Utilities}
642 >
643 > \subsection{\label{appendixSection:Dump2XYZ}Dump2XYZ}
644 >
645 > {\tt Dump2XYZ} can transform an OOPSE dump file into a xyz file
646 > which can be opened by other molecular dynamics viewers such as Jmol
647 > and VMD\cite{Humphrey1996}. The options available for Dump2XYZ are
648 > as follows:
649 >
650 >
651 > \begin{longtable}[c]{|EFG|}
652 > \caption{Dump2XYZ Command-line Options}
653 > \\ \hline
654 > {\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline
655 > \endhead
656 > \hline
657 > \endfoot
658 >  -h & {\tt -{}-help} &                        Print help and exit \\
659 >  -V & {\tt -{}-version} &                     Print version and exit \\
660 >  -i & {\tt -{}-input}  &             input dump file \\
661 >  -o & {\tt -{}-output} &             output file name \\
662 >  -n & {\tt -{}-frame}   &                 print every n frame  (default=`1') \\
663 >  -w & {\tt -{}-water}       &                 skip the the waters  (default=off) \\
664 >  -m & {\tt -{}-periodicBox} &                 map to the periodic box  (default=off)\\
665 >  -z & {\tt -{}-zconstraint}  &                replace the atom types of zconstraint molecules  (default=off) \\
666 >  -r & {\tt -{}-rigidbody}  &                  add a pseudo COM atom to rigidbody  (default=off) \\
667 >  -t & {\tt -{}-watertype} &                   replace the atom type of water model (default=on) \\
668 >  -b & {\tt -{}-basetype}  &                   using base atom type  (default=off) \\
669 >     & {\tt -{}-repeatX}  &                 The number of images to repeat in the x direction  (default=`0') \\
670 >     & {\tt -{}-repeatY} &                 The number of images to repeat in the y direction  (default=`0') \\
671 >     &  {\tt -{}-repeatZ}  &                The number of images to repeat in the z direction  (default=`0') \\
672 >  -s & {\tt -{}-selection} & By specifying {\tt -{}-selection}=``selection command'' with Dump2XYZ, the user can select an arbitrary set of StuntDoubles to be
673 > converted. \\
674 >     & {\tt -{}-originsele} & By specifying {\tt -{}-originsele}=``selection command'' with Dump2XYZ, the user can re-center the origin of the system around a specific StuntDouble \\
675 >     & {\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}.
676 > \end{longtable}
677 >
678 > \subsection{\label{appendixSection:hydrodynamics}Hydro}
679 >
680 > {\tt Hydro} can calculate resistance and diffusion tensors at the
681 > center of resistance. Both tensors at the center of diffusion can
682 > also be reported from the program, as well as the coordinates for
683 > the beads which are used to approximate the arbitrary shapes. The
684 > options available for Hydro are as follows:
685 > \begin{longtable}[c]{|EFG|}
686 > \caption{Hydrodynamics Command-line Options}
687 > \\ \hline
688 > {\bf option} & {\bf verbose option} & {\bf behavior} \\ \hline
689 > \endhead
690 > \hline
691 > \endfoot
692 >  -h & {\tt -{}-help} &                        Print help and exit \\
693 >  -V & {\tt -{}-version} &                     Print version and exit \\
694 >  -i & {\tt -{}-input}  &             input dump file \\
695 >  -o & {\tt -{}-output} &             output file prefix  (default=`hydro') \\
696 >  -b & {\tt -{}-beads}  &                   generate the beads only, hydrodynamics calculation will not be performed (default=off)\\
697 >     & {\tt -{}-model}  &                 hydrodynamics model (supports ``AnalyticalModel'', ``RoughShell'' and ``BeadModel'') \\
698 > \end{longtable}

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