UNIX Programs Research Articles

The MADAG Strategy for Fault Location Techniques

Spectrum-based fault localization (SBFL), which utilizes spectrum information of test cases to calculate the suspiciousness of each statement in a program, can reduce developers’ effort. However, applying redundant test cases from a test suite to fault localization incurs a heavy burden, especially in a restricted resource environment, and it is expensive and infeasible to inspect the results of each test input. Prioritizing/selecting appropriate test cases is important to enable the practical application of the SBFL technique. In addition, we must ensure that applying the selected tests to SBFL can achieve approximately the effectiveness of fault localization with whole tests. This paper presents a test case prioritization/selection strategy, namely the Minimal Aggregate of the Diversity of All Groups (MADAG). The MADAG strategy prioritizes/selects test cases using information on the diversity of the execution trace of each test case. We implemented and applied the MADAG strategy to 233 faulty versions of the Siemens and UNIX programs from the Software-artifact Infrastructure Repository. The experiments show that (1) the MADAG strategy uses only 8.99 and 14.27 test cases, with an average of 18, from the Siemens and UNIX test suites, respectively, and the SBFL technique has approximate effectiveness for fault localization on all test cases and outperforms the previous best test case prioritization method; (2) we verify that applying whole tests from the test suite may not achieve the better effectiveness in fault localization compared with the tests selected by MADAG strategy.

A low-overhead, value-tracking approach to information flow security

Context:Sensitive information such as passwords often leaks inadvertently because of implementation defects.Objective:Our objective is to use dynamic techniques to prevent information leakage before it occurs. We also aim to develop techniques that incur low overheads, and are safe in the presence of aliasing.Method:We use a dynamic approach to track secret values and safe locations. We assume that programs have annotations which identify values and locations that need to be protected against disclosure. We instrument a program with statements that record relevant values and locations and assertions to relevant assignments to determine if they leak information. At run-time the values being assigned to unsafe locations are analysed. If a particular assignment leads to information leakage an assertion violation is triggered. We evaluate our approach by experimentation which uses our prototype implementation for C programs to analyse security-oriented UNIX utilities and programs chosen from the SPEC CPU datasets.Results:Our experiments show that the overhead to detect problems such as password disclosure in real software does not exceed 1%. The overheads associated with detection of CWE security vulnerabilities in real applications are still acceptable; however, tracking a large number of values incurs higher overheads (over 10 times in certain cases).Conclusion:Our dynamic approach to detecting information leaks can be used in various contexts. For a program that tracks only a limited number of values the overhead is marginal. Thus, our instrumentation can be used in release versions. However, if an application has a large number of secret values, our technique is useful in a testing phase. The overheads in this case are too high for a real use, but still within an acceptable range to be used for detection of potential leaks during testing.

An Approach for Cluster-Based Retrieval of Tests Using Cover-Coefficients

Retrieving relevant test cases is a recurring theme in software validation. We present an approach for cluster-based retrieval of test cases for software validation. The approach uses a probabilistic notion of coverage among line-based test profiles and can potentially discover groups of test cases executing a small number of unique lines. The distribution of lines across test profiles are analyzed to determine the number of clusters and generate a clustering structure without any additional user input. We also propose a novel and simple approach to identify test cases that are affected by software changes based on test profiles. It is shown that the clustering structures generated can be used to select affected tests economically to produce high quality regression test suites. The approach is applied to four unix utility programs from a popular testing benchmark. Our results show that the generated number of clusters and their average sizes closely track their estimates based on test profiles. The retrieval of affected tests using the clustering structure is economical and produces a good quality regression test suite.

State dependency probabilistic model for fault localization

ContextFault localization is an important and expensive activity in software debugging. Previous studies indicated that statistically-based fault-localization techniques are effective in prioritizing the possible faulty statements with relatively low computational complexity, but prior works on statistical analysis have not fully investigated the behavior state information of each program element. ObjectiveThe objective of this paper is to propose an effective fault-localization approach based on the analysis of state dependence information between program elements. MethodIn this paper, state dependency is proposed to describe the control flow dependence between statements with particular states. A state dependency probabilistic model uses path profiles to analyze the state dependency information. Then, a fault-localization approach is proposed to locate faults by differentiating the state dependencies in passed and failed test cases. ResultsWe evaluated the fault-localization effectiveness of our approach based on the experiments on Siemens programs and four UNIX programs. Furthermore, we compared our approach with current state-of-art fault-localization methods such as SOBER, Tarantula, and CP. The experimental results show that, our approach can locate more faults than the other methods in every range on Siemens programs, and the overall efficiency of our approach in the range of 10–30% of analyzed source code is higher than the other methods on UNIX programs. ConclusionOur studies show that our approach consistently outperforms the other evaluated techniques in terms of effectiveness in fault localization on Siemens programs. Moreover, our approach is highly effective in fault localization even when very few test cases are available.

MicrOMEGAs_3: A program for calculating dark matter observables

micrOMEGAs is a code to compute dark matter observables in generic extensions of the standard model. This new version of micrOMEGAs is a major update which includes a generalization of the Boltzmann equations to accommodate models with asymmetric dark matter or with semi-annihilation and a first approach to a generalization of the thermodynamics of the Universe in the relic density computation. Furthermore a switch to include virtual vector bosons in the final states in the annihilation cross sections or relic density computations is added. Effective operators to describe loop-induced couplings of Higgses to two-photons or two-gluons are introduced and reduced couplings of the Higgs are provided allowing for a direct comparison with recent LHC results. A module that computes the signature of DM captured in celestial bodies in neutrino telescopes is also provided. Moreover the direct detection module has been improved as concerns the implementation of the strange “content” of the nucleon. New extensions of the standard model are included in the distribution. Program summaryTitle of program: micrOMEGAs3.Program obtainable from:http://lapth.cnrs.fr/micromegasComputers for which the program is designed and others on which it has been tested: PC, MacOperating systems under which the program has been tested : UNIX (Linux, Darwin)Programming language used: C and FortranMemory required to execute with typical data: 50 MB depending on the number of processes required.No. of processors used: 1Has the code been vectorized or parallelized: noNo. of bytes in distributed program, including test data: 70736 kBExternal routines/libraries used: noCPC Program Library subprograms used: CalcHEP, SuSpect, NMSSMTools, CPSuperH, LoopTools, HiggsBoundsCatalogue identifier of previous version: ADQR_v1_3Journal reference of previous version: Comput. Phys. Comm. 182 (2011) 842Does the new version supersede the previous version: yesNature of physical problem: Calculation of the relic density and direct and indirect detection rates of the lightest stable particle in a generic new model of particle physics.Method of solution: In numerically solving the evolution equation for the density of dark matter, relativistic formulae for the thermal average are used. All tree-level processes for annihilation and coannihilation of new particles in the model are included as well as some 3-body final states. The cross-sections for all processes are calculated exactly with CalcHEP after definition of a model file. The propagation of the charged cosmic rays is solved within a semi-analytical two-zone model.Reasons for the new version: There are many experiments that are currently searching for the remnants of dark matter annihilation and the relic density is determined precisely from cosmological measurements. In this version we add the computation of dark matter signals in neutrino telescopes, we generalize the Boltzmann equations so as to take into account a larger class of dark matter models and improve the precision in the prediction of the relic density for DM masses that are below the W mass. We compute the signal strength for Higgs production in different channels to compare with the results of the LHC.Summary of revisions:•Generalization of the Boltzmann equations to include asymmetric dark matter and semi-annihilations: the DM asymmetry is taken into account when computing direct/indirect detection rates.•Incorporating loop-induced decays of Higgs particles to two-photons and two-gluons, and computing the signal strength for Higgs production in various channels that can be compared to results from LHC searches.•New module for neutrino signature from DM capture in the Sun and the Earth•Annihilation cross sections for some selected 3-body processes in addition to the 2-body tree-level processes. The 3-body option can be included in the computation of the relic density and/or for annihilation of dark matter in the galaxy.•Possibility of using different tables for the effective degrees of freedom in the early Universe•Annihilation cross sections for the loop induced processes γγ and γZ0 in the NMSSM and the CPVMSSM•New function for incorporating DM clumps•New function to define the strange quark content of the nucleon•The LanHEP source code for new models is included•New models with scalar DM are included (Inert doublet model and model with Z3 symmetry)•New implementation of the NMSSM which uses the Higgs self-couplings and the particle spectrum calculated in NMSSMTools_4.1•New versions of spectrum generators used in the MSSM (Suspect_2.4.1) and in the CPVMSSM (CPsuperH2.3)•Extended routines for flavor physics in the MSSM•New facilities to compute DM observables independently of the model•Update in interface tools to read files produced by other codes, this allows easy interface to other codesTypical running time: 4 sUnusual features of the program: Depending on the parameters of the model, the program generates additional new code, compiles it and loads it dynamically.

Let’s Leave the Bias to the Mainstream Media: A Wikipedia Community Fighting for Information Neutrality

Let’s Leave the Bias to the Mainstream Media: A Wikipedia Community Fighting for Information Neutrality

SIMULATION AND EMULIATION IN NCTUNS

The features of NCTUns simulation environment are presented along with developed models, showing the advantages of this simulation tool. NCTUns gives the ability to reuse kernel TCP/IP stack and therefore to simplify and speedup the simulations, also to make use of any UNIX commands or programs. Presented wireless multihop transmission model for delay and jitter investigation, also wireless multihop video transmission model. Model, employing emulation, enables to evaluate the impact of simulated network not only on flow characteristics, but also on live application reception.

QRAP: A numerical code for projected (Q)uasiparticle (RA)ndom (P)hase approximation

A computer code for quasiparticle random phase approximation – QRPA and projected quasiparticle random phase approximation – PQRPA models of nuclear structure is explained in details. The residual interaction is approximated by a simple δ-force. An important application of the code consists in evaluating nuclear matrix elements involved in neutrino–nucleus reactions. As an example, cross sections for 56Fe and 12C are calculated and the code output is explained. The application to other nuclei and the description of other nuclear and weak decay processes are also discussed. Program summary Title of program: QRAP ( Quasiparticle RAndom Phase approximation) Computers: The code has been created on a PC, but also runs on UNIX or LINUX machines Operating systems: WINDOWS or UNIX Program language used: Fortran-77 Memory required to execute with typical data: 16 Mbytes of RAM memory and 2 MB of hard disk space No. of lines in distributed program, including test data, etc.: ∼ 8000 No. of bytes in distributed program, including test data, etc.: ∼ 256 kB Distribution format: tar.gz Nature of physical problem: The program calculates neutrino– and antineutrino–nucleus cross sections as a function of the incident neutrino energy, and muon capture rates, using the QRPA or PQRPA as nuclear structure models. Method of solution: The QRPA, or PQRPA, equations are solved in a self-consistent way for even–even nuclei. The nuclear matrix elements for the neutrino–nucleus interaction are treated as the beta inverse reaction of odd–odd nuclei as function of the transfer momentum. Typical running time: ≈ 5 min on a 3 GHz processor for Data set 1.

MicrOMEGAs 2.0: A program to calculate the relic density of dark matter in a generic model

micrOMEGAs 2.0 is a code which calculates the relic density of a stable massive particle in an arbitrary model. The underlying assumption is that there is a conservation law like R-parity in supersymmetry which guarantees the stability of the lightest odd particle. The new physics model must be incorporated in the notation of CalcHEP, a package for the automatic generation of squared matrix elements. Once this is done, all annihilation and coannihilation channels are included automatically in any model. Cross-sections at v = 0 , relevant for indirect detection of dark matter, are also computed automatically. The package includes three sample models: the minimal supersymmetric standard model (MSSM), the MSSM with complex phases and the NMSSM. Extension to other models, including non-supersymmetric models, is described. Program summary Title of program:micrOMEGAs2.0 Catalogue identifier:ADQR_v2_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADQR_v2_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computers for which the program is designed and others on which it has been tested:PC, Alpha, Mac, Sun Operating systems under which the program has been tested:UNIX (Linux, OSF1, SunOS, Darwin, Cygwin) Programming language used:C and Fortran Memory required to execute with typical data:17 MB depending on the number of processes required No. of processors used:1 Has the code been vectorized or parallelized:no No. of lines in distributed program, including test data, etc.:91 778 No. of bytes in distributed program, including test data, etc.:1 306 726 Distribution format:tar.gz External routines/libraries used:no Catalogue identifier of previous version:ADQR_v1_3 Journal reference of previous version:Comput. Phys. Comm. 174 (2006) 577 Does the new version supersede the previous version:yes Nature of physical problem:Calculation of the relic density of the lightest stable particle in a generic new model of particle physics. Method of solution: In numerically solving the evolution equation for the density of dark matter, relativistic formulae for the thermal average are used. All tree-level processes for annihilation and coannihilation of new particles in the model are included. The cross-sections for all processes are calculated exactly with CalcHEP after definition of a model file. Higher-order QCD corrections to Higgs couplings to quark pairs are included. Reasons for the new version:There are many models of new physics that propose a candidate for dark matter besides the much studied minimal supersymmetric standard model. This new version not only incorporates extensions of the MSSM, such as the MSSM with complex phases, or the NMSSM which contains an extra singlet superfield but also gives the possibility for the user to incorporate easily a new model. For this the user only needs to redefine appropriately a new model file. Summary of revisions: • Possibility to include in the package any particle physics model with a discrete symmetry that guarantees the stability of the cold dark matter candidate (LOP) and to compute the relic density of CDM. • Compute automatically the cross-sections for annihilation of the LOP at small velocities into SM final states and provide the energy spectra for γ , e + , p ¯ , ν final states. • For the MSSM with input parameters defined at the GUT scale, the interface with any of the spectrum calculator codes reads an input file in the SUSY Les Houches Accord format (SLHA). • Implementation of the MSSM with complex parameters (CPV-MSSM) with an interface to CPsuperH to calculate the spectrum. • Routine to calculate the electric dipole moment of the electron in the CPV-MSSM. • In the NMSSM, new interface compatible with NMHDECAY2.1. Typical running time:0.2 sec Unusual features of the program:Depending on the parameters of the model, the program generates additional new code, compiles it and loads it dynamically.

USFKAD: An expert system for partial differential equations

The computation of the solution, by the separation of variables process, of the Poisson, diffusion, and wave equations in rectangular, cylindrical, or spherical coordinate systems, with Dirichlet, Neumann, or Robin boundary conditions, can be carried out in the time, Laplace, or frequency domains by a decision-tree process, using a library of eigenfunctions. We describe an expert system, USFKAD, that has been constructed for this purpose. Program summary Title of program:USFKAD Catalogue identifier:ADYN_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADYN_v1_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions:none Operating systems under which the program has been tested: Windows, UNIX Programming language used:C++, LaTeX No. of lines in distributed program, including test data, etc.: 11 699 No. of bytes in distributed program, including test data, etc.: 537 744 Memory required to execute with typical data: 1.3 Megabytes Distribution format: tar.gz Nature of mathematical problem: Analytic solution of Poisson, diffusion, and wave equations Method of solution: Eigenfunction expansions Restrictions concerning the complexity of the problem: A few rarely-occurring singular boundary conditions are unavailable, but they can be approximated by regular boundary value problems to arbitrary accuracy. Typical running time:1 second Unusual features of the program: Solutions are obtained for Poisson, diffusion, or wave PDEs; homogeneous or nonhomogeneous equations and/or boundary conditions; rectangular, cylindrical, or spherical coordinates; time, Laplace, or frequency domains; Dirichlet, Neumann, Robin, singular, periodic, or incoming/outgoing boundary conditions. Output is suitable for pasting into LaTeX documents.

GR@PPA 2.7 event generator for [formula omitted] collisions

The GR@PPA event generator has been updated to version 2.7. This distribution provides event generators for V ( W or Z) + jets (⩽4 jets), V V + jets (⩽2 jets) and QCD multi-jet (⩽4 jets) production processes at pp and p p ¯ collisions, in addition to the four bottom quark productions implemented in our previous work (GR@PPA_4b). Also included are the top-pair and top-pair + jet production processes, where the correlation between the decay products are fully reproduced at the tree level. Namely, processes up to seven-body productions can be simulated, based on ordinary Feynman diagram calculations at the tree level. In this version, the GR@PPA framework and the process dependent matrix-element routines are separately provided. This makes it easier to add further new processes, and allows users to make a choice of processes to implement. This version also has several new features to handle complicated multi-body production processes. A systematic way to combine many subprocesses to a single base-subprocess has been introduced, and a new method has been adopted to calculate the color factors of complicated QCD processes. They speed up the calculation significantly. Program summary Title of program:GR@PPA (v2.7) Catalogue identifier:ADRH_v2_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADRH_v2_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Operating system under which the program has been tested:UNIX Programming language used:Fortran77 Other CPC library programs required:PYTHIA, HERWIG, BASES, SPRING Memory required to execute with typical data:56.5 kwords for an integration, 74.6 kwords for an event generation Number of bytes in distributed program, including test data, etc.: 570 587 No. of lines in distributed program, including test data, etc.:143 327 Distribution format:tar.gz Nature of physical problem:The multi-legs interaction processes have become more important with increasing the colliding energy available at the high energy collider experiments. At hadron-collider experiments, since thousands of Feynman diagrams contributes in the single interaction process, the faster and more stable calculation to obtain the results is desirable. Method of solution: GR@PPA is an event generator for V ( W or Z) + jets (⩽ 4 jets), V V + jets (⩽ 2 jets) and QCD multi-jet (⩽ 4 jets) production processes at pp and p p ¯ collisions, in addition to the four bottom quark productions implemented in our previous work (GR@PPA_4b). Also included are the top-pair and top-pair + jet production processes. In this version, the GR@PPA framework and the process dependent matrix-element routines are separately provided. This makes it easier to add further new processes, and allows users to make a choice of processes to implement. This version also has several new features to handle complicated multi-body production processes. A systematic way to combine many subprocesses to a single base-subprocess has been introduced, and a new method has been adopted to calculate the color factors of complicated QCD processes. They speed up the calculation significantly. Restrictions on the complexity of the program: The interference between decay fermions from the boson and those from other sources is ignored in the diagram calculation. Typical running time: 2 hours for a cross-section integration and 200 msec per 1 event for an event generation.

Revised and extended Utilities for the Ratip package

Revised and extended Utilities for the Ratip package

MOMDIS: a Glauber model computer code for knockout reactions

A computer program is described to calculate momentum distributions in stripping and diffraction dissociation reactions. A Glauber model is used with the scattering wavefunctions calculated in the eikonal approximation. The program is appropriate for knockout reactions at intermediate energy collisions ( 30 MeV ⩽ E lab / nucleon ⩽ 2000 MeV ). It is particularly useful for reactions involving unstable nuclear beams, or exotic nuclei (e.g., neutron-rich nuclei), and studies of single-particle occupancy probabilities (spectroscopic factors) and other related physical observables. Such studies are an essential part of the scientific program of radioactive beam facilities, as in for instance the proposed RIA (Rare Isotope Accelerator) facility in the US. Program summary Title of program: MOMDIS (MOMentum DIStributions) Catalogue identifier:ADXZ_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADXZ_v1_0 Computers: The code has been created on an IBM-PC, but also runs on UNIX or LINUX machines Operating systems: WINDOWS or UNIX Program language used: Fortran-77 Memory required to execute with typical data: 16 Mbytes of RAM memory and 2 MB of hard disk space No. of lines in distributed program, including test data, etc.: 6255 No. of bytes in distributed program, including test data, etc.: 63 568 Distribution format: tar.gz Nature of physical problem: The program calculates bound wavefunctions, eikonal S-matrices, total cross-sections and momentum distributions of interest in nuclear knockout reactions at intermediate energies. Method of solution: Solves the radial Schrödinger equation for bound states. A Numerov integration is used outwardly and inwardly and a matching at the nuclear surface is done to obtain the energy and the bound state wavefunction with good accuracy. The S-matrices are obtained using eikonal wavefunctions and the “t- ρρ” method to obtain the eikonal phase-shifts. The momentum distributions are obtained by means of a Gaussian expansion of integrands. Main integrals are performed with the Simpson's method. Typical running time: Almost all CPU time is consumed by calculations of integrals, specially for transverse momentum distributions which involves multiple integral loops. It takes up to 30 min on a 2 GHz Intel P4-processor machine.

A programmable optimization environment using the GAMESS-US and MERLIN/MCL packages. Applications on intermolecular interaction energies

The Merlin/MCL optimization environment and the GAMESS-US package were combined so as to offer an extended and efficient quantum chemistry optimization system, capable of implementing complex optimization strategies for generic molecular modeling problems. A communication and data exchange interface was established between the two packages exploiting all Merlin features such as multiple optimizers, box constraints, user extensions and a high level programming language. An important feature of the interface is its ability to perform dimer computations by eliminating the basis set superposition error using the counterpoise (CP) method of Boys and Bernardi. Furthermore it offers CP-corrected geometry optimizations using analytic derivatives. The unified optimization environment was applied to construct portions of the intermolecular potential energy surface of the weakly bound H-bonded complex C 6H 6–H 2O by utilizing the high level Merlin Control Language. The H-bonded dimer HF–H 2O was also studied by CP-corrected geometry optimization. The ab initio electronic structure energies were calculated using the 6-31G ** basis set at the Restricted Hartree–Fock and second-order Moller–Plesset levels, while all geometry optimizations were carried out using a quasi-Newton algorithm provided by Merlin. Program summary Title of program: MERGAM Catalogue identifier:ADYB_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADYB_v1_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer for which the program is designed and others on which it has been tested: The program is designed for machines running the UNIX operating system. It has been tested on the following architectures: IA32 (Linux with gcc/g77 v.3.2.3), AMD64 (Linux with the Portland group compilers v.6.0), SUN64 (SunOS 5.8 with the Sun Workshop compilers v.5.2) and SGI64 (IRIX 6.5 with the MIPSpro compilers v.7.4) Installations: University of Ioannina, Greece Operating systems or monitors under which the program has been tested: UNIX Programming language used: ANSI C, ANSI Fortran-77 No. of lines in distributed program, including test data, etc.:11 282 No. of bytes in distributed program, including test data, etc.: 49 458 Distribution format: tar.gz Memory required to execute with typical data: Memory requirements mainly depend on the selection of a GAMESS-US basis set and the number of atoms No. of bits in a word: 32 No. of processors used: 1 Has the code been vectorized or parallelized?: no Nature of physical problem: Multidimensional geometry optimization is of great importance in any ab initio calculation since it usually is one of the most CPU-intensive tasks, especially on large molecular systems. For example, the geometric and energetic description of van der Waals and weakly bound H-bonded complexes requires the construction of related important portions of the multidimensional intermolecular potential energy surface (IPES). So the various held views about the nature of these bonds can be quantitatively tested. Method of solution: The Merlin/MCL optimization environment was interconnected with the GAMESS-US package to facilitate geometry optimization in quantum chemistry problems. The important portions of the IPES require the capability to program optimization strategies. The Merlin/MCL environment was used for the implementation of such strategies. In this work, a CP-corrected geometry optimization was performed on the HF–H 2O complex and an MCL program was developed to study portions of the potential energy surface of the C 6H 6–H 2O complex. Restrictions on the complexity of the problem: The Merlin optimization environment and the GAMESS-US package must be installed. The MERGAM interface requires GAMESS-US input files that have been constructed in Cartesian coordinates. This restriction occurs from a design-time requirement to not allow reorientation of atomic coordinates; this rule holds always true when applying the COORD = UNIQUE keyword in a GAMESS-US input file. Typical running time: It depends on the size of the molecular system, the size of the basis set and the method of electron correlation. Execution of the test run took approximately 5 min on a 2.8 GHz Intel Pentium CPU.

BCVEGPY2.0: An upgraded version of the generator BCVEGPY with the addition of hadroproduction of the P-wave [formula omitted] states

The generator BCVEGPY is upgraded by adding the hadroproduction of the $P$-wave excited $B_c$ states (denoted by $B_{cJ,L=1}^*$ or by $h_{B_c}$ and $\chi_{B_c}$) and by improving some features of the original one as well. We denote it as BCVEGPY2.0. The $P$-wave production is also calculated by taking only the dominant gluon-gluon fusion mechanism (with the subprocess $gg\to B_{cJ,L=1}^*+\bar{c}+b$ being dominated) into account as that for $S$-wave. In order to make the addendum piece of the upgraded generator as compact as possible so as to increase its efficiency, we manipulate the amplitude as compact as possible with FDC (a software for generating Feynman diagrams and the algebra amplitudes, and for manipulating algebra formulae analytically etc) and certain simplification techniques. The correctness of the program is tested by checking the gauge invariance of the amplitude and by comparing the numerical results with the existent ones in the literature carefully.

Bookshelf

Understanding Open Source Licensing: Three How-To Guides Joel West Reviews of Open Source Software Law by Rod Dixon, Understanding Open Source and Free Software Licensing by Andrew M. St. Laurent, and Open Source Licensing by Lawrence Rosen A Complete Code-Reading Source Angela Jury Review of Code Reading: The Open Source Perspective by Diomidis Spinellis Technological Account of Grid Computing Shubhashis Sengupta Review of Grid Computing by Joshy Joseph and Craig Fellenstein The Philosophy of Good Programming Stratton Penberthy Review of The Art of UNIX Programming by Eric S. Raymond

Class library ranlip for multivariate nonuniform random variate generation

This paper describes generation of nonuniform random variates from Lipschitz-continuous densities using acceptance/rejection, and the class library ranlip which implements this method. It is assumed that the required distribution has Lipschitz-continuous density, which is either given analytically or as a black box. The algorithm builds a piecewise constant upper approximation to the density (the hat function), using a large number of its values and subdivision of the domain into hyperrectangles. The class library ranlip provides very competitive preprocessing and generation times, and yields small rejection constant, which is a measure of efficiency of the generation step. It exhibits good performance for up to five variables, and provides the user with a black box nonuniform random variate generator for a large class of distributions, in particular, multimodal distributions. It will be valuable for researchers who frequently face the task of sampling from unusual distributions, for which specialized random variate generators are not available. Program summary Title of program: Ranlip Catalogue number: ADVP Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVP Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computers: IBM PC; DEC Alpha Operating systems under which the program has been tested: Windows XP, Linux, Unix Programming language used: C++ Memory required to execute with typical data: 32M No. of bits in a word: 32 No. of processors used: 1 Has the code been vectorized?: No No. of lines in distributed program, including test data, etc.: 52 160 No. of bytes in distributed program, including test data, etc.: 392 625 Distribution format: tar.gz Nature of physical problem:This program allows one to generate nonuniform random vectors from a variety of distributions (especially multimodal), using acceptance/rejection approach. Suitable for non-standard distributions for up to five variables. Method of solution:Assuming Lipschitz-continuous density, a tight overestimate (the hat function) is computed. Then random variates are generated using acceptance/rejection approach. Restrictions on the complexity of the problem:If the number of variables exceeds five, computation of the overestimate is inefficient. Typical running time:Preprocessing 1–5000 s, generation 5 – 20 × 10 −6 s .

Cuba—a library for multidimensional numerical integration

The Cuba library provides new implementations of four general-purpose multidimensional integration algorithms: Vegas, Suave, Divonne, and Cuhre. Suave is a new algorithm, Divonne is a known algorithm to which important details have been added, and Vegas and Cuhre are new implementations of existing algorithms with only few improvements over the original versions. All four algorithms can integrate vector integrands and have very similar Fortran, C/C++, and Mathematica interfaces. Program summary Title of program: Cuba Catalogue identifier: ADVH Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVH Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer for which the program is designed and others on which is has been tested: Designed for: all platforms with an ISO C99 C compiler Tested on: x86 (Linux/gcc), Alpha (Tru64 Unix/gcc) Operating systems or monitors under which the program has been tested: Linux, Tru64 Unix Programming language used: C Memory required to execute with typical data: 1M words No. of bits in a word: 8 No. of processors used: 1 Has the code been vectorized or parallelized?: Not yet No. of lines in distributed program, including test data, etc.: 9380 No. of bytes in distributed program, including test data, etc.: 131 293 Distribution format: tar.gz Nature of the physical problem: Multidimensional numerical integrations, e.g., of phase spaces. Method of solution: The Cuba library contains the four algorithms Vegas, Suave, Divonne, and Cuhre with the following characteristics: Routine Basic integration method Algorithm type Variance reduction Vegas Sobol quasi-random sample Monte Carlo importance sampling Suave Sobol quasi-random sample Monte Carlo globally adaptive subdivision Divonne Korobov quasi-random sample Monte Carlo stratified sampling, or Sobol quasi-random sample Monte Carlo aided by methods from or cubature rules deterministic numerical optimization Cuhre cubature rules deterministic globally adaptive subdivision Typical running time: Varies greatly depending on the integrand and the chosen accuracy. Can range from seconds to days. Unusual features of the program: Coherent interface in Fortran, C/C++, and Mathematica. Can integrate vector integrands.

The effects of individual differences on CS2 course performance across universities

Research is presented that examined the effects of various measures of prior computer science experience and cognitive abilities on overall performance in a CS2 course. Participants selected from the CS2 course at two southeastern state universities were used within this study, resulting in a sample size of 161 (School A, n = 76; School B, n = 85). School A is a mid-sized comprehensive university and School B is a large research-intensive university.Self-reported data were collected on measures of experience in object-oriented processing, UNIX programming, web design, computing platforms, and various CS experience. Further, cognitive abilities measures of spatial orientation, visualization, logical reasoning, and flexibility were administered.The results show that the schools significantly differed on all measures of cognitive ability and most measures of prior computer science experience. The schools also differed on the extent to which these measures were related to overall course performance. The results suggest that, for school A, the cognitive ability visualization and the prior computer science experience measure of OO processing were significantly related to course performance. However, when examining school B, no measures were found significant.

New vibration–rotation code for tetraatomic molecules exhibiting wide-amplitude motion: WAVR4

A general computational method for the accurate calculation of rotationally and vibrationally excited states of tetraatomic molecules is developed. The resulting program is particularly appropriate for molecules executing wide-amplitude motions and isomerizations. The program offers a choice of coordinate systems based on Radau, Jacobi, diatom–diatom and orthogonal satellite vectors. The method includes all six vibrational dimensions plus three rotational dimensions. Vibration–rotation calculations with reduced dimensionality in the radial degrees of freedom are easily tackled via constraints imposed on the radial coordinates via the input file. Program summary Title of program: WAVR4 Catalogue number: ADUN Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADUN Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: Persons requesting the program must sign the standard CPC nonprofit use license Computer: Developed under Tru64 UNIX, ported to Microsoft Windows and Sun Unix Operating systems under which the program has been tested: Tru64 Unix, Microsoft Windows, Sun Unix Programming language used: Fortran 90 Memory required to execute with typical data: case dependent No. of lines in distributed program, including test data, etc.: 11 937 No. of bytes in distributed program, including test data, etc.: 84 770 Distribution format: tar.gz Nature of physical problem: WAVR4 calculates the bound ro-vibrational levels and wavefunctions of a tetraatomic system using body-fixed coordinates based on generalised orthogonal vectors. Method of solution: The angular coordinates are treated using a finite basis representation (FBR) based on products of spherical harmonics. A discrete variable representation (DVR) [1] based on either Morse-oscillator-like or spherical-oscillator functions [2] is used for the radial coordinates. Matrix elements are computed using an efficient Gaussian quadrature in the angular coordinates and the DVR approximation in the radial coordinates. The solution of the secular problem is carried through a series of intermediate diagonalisations and truncations. Restrictions on the complexity of the problem: (1) The size of the final Hamiltonian matrix that can be practically diagonalised; (2) The DVR approximation for a radial coordinate fails for values of the coordinate near zero—this is remedied only for one radial coordinate by using analytical integration. Typical running time: problem-dependent Unusual features of the program: A user-supplied subroutine to evaluate the potential energy is a program requirement. External routines: BLAS and LAPACK are required.