Date::Calc::XS is a Perl module that is the C/XS part which Date::Calc used to consist of. Date::Calc has become a (pure-Perl) wrapper which tries to load Date::Calc::XS, and failing that, loads Date::Calc::PP (a pure-Perl implementation which is now part of Date::Calc and used to be Date::Pcalc).
LibBi is used for state-space modelling and Bayesian inference on high-performance computer hardware, including multi-core CPUs, many-core GPUs (graphics processing units), and distributed-memory clusters. The staple methods of LibBi are based on sequential Monte Carlo (SMC), also known as particle filtering. These methods include particle Markov chain Monte Carlo (PMCMC) and SMC2. Other methods include the extended Kalman filter and some parameter optimization routines. LibBi consists of a C++ template library and a parser and compiler, written in Perl, for its own modelling language.
Daikon is an implementation of dynamic detection of likely invariants. An invariant is a property (such as "x=2*y+5" or "this.next.prev = this" or "myarray is sorted by <") that holds at a certain point or points in a program. Invariants are often seen in assert statements, documentation, and formal specifications. Invariants can be useful in program understanding and a host of other applications. Daikon runs a program, observes the values that the program computes, and then reports properties that were true over the observed executions. It can detect properties in Java, C, C++, Perl, and IOA programs, in spreadsheet files, and in other data sources.
The Chombo package provides a set of tools for implementing finite difference methods for the solution of partial differential equations on block-structured adaptively refined rectangular grids. Both elliptic and time-dependent modules are included. Support for parallel platforms and standardized self-describing file formats are included.
The number perl script will print the English name of a number. One can print names of extremely large numbers (e.g. 1e1234567). Number can be run on the command line, or as a CGI script when run as 'number.cgi'. Number prints names in both the American and European naming system. It can also print the decimal expansion of a number in either naming system.
The Date::Calc package consists of a (pure-Perl) wrapper which either loads Date::Calc::XS (a separate implementation in C and XS) or Date::Calc::PP (a pure-Perl implementation which is part of the Date::Calc package). The Date::Calc::XS and Date::Calc::PP modules perform all kinds of date calculations based on the Gregorian calendar (the one used in all Western countries today), according to relevant norms and standards: ISO/R 2015-1971, DIN 1355 and, to some extent, ISO 8601 (where applicable). The package is designed as an efficient toolbox, not a bulky ready-made application. It provides extensive documentation and examples of use, multi-language support, and special functions for business needs.
Condorcet with Dual Dropping is a ranking system for deciding single or multi-winner contests (elections) using voted preference (or approval) ballot list or pairwise tally matrix. It computes the Cloneproof Schwartz Sequential Dropping (CSSD) and Tideman's Ranked Pair (RP) results for each contest round, and selects the combined CSSD and RP outcome with the lowest overall dropping cost. There are options to compute just the CSSD, RP, or Minimum Dropping Cost outcome, various optional pair rank and winner tie-breakers, and alternative measures of dropping cost (winning votes and/or margin). It comes as a console program and CGI executable.
Trad4 is a fully concurrent, thread safe, graph based programming language that scales linearly on multiple cores. It is initially intended for deployment in the financial industry to model real-time risk. Trad4 is proposed as an alternative to the Von Neumann model of computer architecture. It is a new way of arranging programs in memory and a new style of flow-of-control.