Coinduction

In computer science, coinduction is a technique for defining and proving properties of systems of concurrent interacting objects.

Coinduction is the mathematical dual to structural induction. Coinductively defined types are known as codata and are typically infinite data structures, such as streams.

As a definition or specification, coinduction describes how an object may be "observed", "broken down" or "destructed" into simpler objects. As a proof technique, it may be used to show that an equation is satisfied by all possible implementations of such a specification.

To generate and manipulate codata, one typically uses corecursive functions, in conjunction with lazy evaluation. Informally, rather than defining a function by pattern-matching on each of the inductive constructors, one defines each of the "destructors" or "observers" over the function result.

In programming, the co-logic paradigm (Co-LP for brevity) "is a natural generalization of logic programming and coinductive logic programming, which in turn generalizes other extensions of logic programming, such as infinite trees, lazy predicates, and concurrent communicating predicates. Co-LP has applications to rational trees, verifying infinitary properties, lazy evaluation, concurrent LP, model checking, bisimilarity proofs, etc." Experimental implementations of Co-LP are available from U.T.Dallas and in Logtalk (for examples see ) and SWI-Prolog.

Committee on Data for Science and Technology

The Committee on Data for Science and Technology (CODATA) was established in 1966 as an interdisciplinary committee of the International Council for Science. It seeks to improve the compilation, critical evaluation, storage, and retrieval of data of importance to science and technology.

CODATA sponsors the CODATA international conference every two years.

Task Group on Fundamental Constants

CODATA is best known for (and sometimes confused with) its Task Group on Fundamental Constants. Established in 1969, its purpose is to periodically provide the international scientific and technological communities with an internationally accepted set of values of the fundamental physical constants and closely related conversion factors for use worldwide.

The first such CODATA set was published in 1973. Later versions are named based on the year of the data incorporated; the 1986 CODATA (published April 1987) used data up to 1 January 1986. All subsequent releases use data up to the end of the stated year, and are necessarily published a year or two later: 1998 (April 2000), 2002 (January 2005), 2006 (June 2008) and the sixth in 2010 (November 2012). The latest version is Version 7.0 called "2014 CODATA" published on 25 June 2015.