322,911 research outputs found
ROOT, an object oriented data analysis framework
ROOT is an object-oriented framework aimed at solving the data analysis challenges of high-energy physics. Here we discuss the main components of the framework. We begin with an overview describing the framework's organization, the interpreter CINT, its automatic interface to the compiler and linker ACLiC, and an example of a first interactive session. The subsequent sections cover histogramming and fitting. Then, ROOT's solution to storing and retrieving HEP data, building and managing of ROOT files, and designing ROOT trees. Followed by a description of the collection classes, the GUI classes, how to add your own classes to ROOT, and PROOF, ROOT's parallel processing facility
A practical guide to computer simulations
Here practical aspects of conducting research via computer simulations are
discussed. The following issues are addressed: software engineering,
object-oriented software development, programming style, macros, make files,
scripts, libraries, random numbers, testing, debugging, data plotting, curve
fitting, finite-size scaling, information retrieval, and preparing
presentations.
Because of the limited space, usually only short introductions to the
specific areas are given and references to more extensive literature are cited.
All examples of code are in C/C++.Comment: 69 pages, with permission of Wiley-VCH, see http://www.wiley-vch.de
(some screenshots with poor quality due to arXiv size restrictions) A
comprehensively extended version will appear in spring 2009 as book at
Word-Scientific, see http://www.worldscibooks.com/physics/6988.htm
Subclassing errors, OOP, and practically checkable rules to prevent them
This paper considers an example of Object-Oriented Programming (OOP) leading
to subtle errors that break separation of interface and implementations. A
comprehensive principle that guards against such errors is undecidable. The
paper introduces a set of mechanically verifiable rules that prevent these
insidious problems. Although the rules seem restrictive, they are powerful and
expressive, as we show on several familiar examples. The rules contradict both
the spirit and the letter of the OOP. The present examples as well as available
theoretical and experimental results pose a question if OOP is conducive to
software development at all.Comment: 10 pages, 1 LaTeX file; accompanying C++ and Haskell code and
compilation instruction
Database independent Migration of Objects into an Object-Relational Database
This paper reports on the CERN-based WISDOM project which is studying the
serialisation and deserialisation of data to/from an object database
(objectivity) and ORACLE 9i.Comment: 26 pages, 18 figures; CMS CERN Conference Report cr02_01
Real world evaluation of aspect-oriented software development : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Computer Science at Massey University, Palmerston North, New Zealand
Software development has improved over the past decade with the rise in the popularity of the Object-Oriented (OO) development approach. However, software projects continue to grow in complexity and continue to have alarmingly low rates of success. Aspect-Oriented Programming (AOP) is touted to be one solution to this software development problem. It shows promise of reducing programming complexity, making software more flexible and more amenable to change. The central concept introduced by AOP is the aspect. An aspect is used to modularise crosscutting concerns in a similar fashion to the way classes modularise business concerns. A crosscutting concern cannot be modularised in approaches such as OO because the code to realise the concern must be spread throughout the module (e.g. a tracing concent is implemented by adding code to every method in a system). AOP also introduces join points, pointcuts, and advice which are used with aspects to capture crosscutting concerns so they can be localised in a modular unit. OO took approximately 20 years to become a mainstream development approach. AOP was only invented in 1997. This project considers whether AOP is ready for commercial adoption. This requires analysis of the AOP implementations available, tool support, design processes, testing tools, standards, and support infrastructure. Only when AOP is evaluated across all these criteria can it be established whether it is ready to be used in commercial projects. Moreover, if companies are to invest time and money into adopting AOP, they must be aware of the benefits and risks associated with its adoption. This project attempts to quantify the potential benefits in adopting AOP, as well as identifying areas of risk. SolNet Solutions Ltd, an Information Technology (IT) company in Wellington, New Zealand, is used in this study as a target environment for integration of aspects into a commercial development process. SolNet is in the business of delivering large scale enterprise Java applications. To assist in this process they have developed a Common Services Architecture (CSA) containing components that can be reused to reduce risk and cost to clients. However, the CSA is complicated and SolNet have identified aspects as a potential solution to decrease the complexity. Aspects were found to bring substantial improvement to the Service Layer of SolNet. applications, including substantial reductions in complexity and size. This reduces the cost and time of development, as well as the risk associated with the projects. Moreover, the CSA was used in a more consistent fashion making the system easier to understand and maintain, and several crosscutting concerns were modularised as part of a reusable aspect library which could eventually form part of their CSA. It was found that AOP is approaching commercial readiness. However, more work is needed on defining standards for aspect languages and modelling of design elements. The current solutions in this area are commercially viable, but would greatly benefit from a standardised approach. Aspect systems can be difficult to test and the effect of the weaving process on Java serialisation requires further investigation
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