Reduction

Reduction, reduced, or reduce may refer to:

Science

Chemistry

Reduce (computer algebra system)

Reduce is a general-purpose computer algebra system geared towards applications in physics.

The development of the Reduce computer algebra system was started in the 1960s by Anthony C. Hearn. Since then, many scientists from all over the world have contributed to its development under his direction.

Reduce is written entirely in its own LISP dialect called Portable Standard LISP, expressed in an Algol-like syntax called RLISP. The latter is used as a basis for Reduce's user-level language.

Implementations of Reduce are available on most variants of Unix, Linux, Microsoft Windows, or Apple Macintosh systems by using an underlying Portable Standard LISP or Codemist Standard LISP implementation.

Reduce was open sourced on December 2008 and is available for free under a modified BSD license on SourceForge. Previously it had cost $695.

See also

References

External links

Reduction (complexity)

In computability theory and computational complexity theory, a reduction is an algorithm for transforming one problem into another problem. A reduction from one problem to another may be used to show that the second problem is at least as difficult as the first.

Intuitively, problem A is reducible to problem B if an algorithm for solving problem B efficiently (if it existed) could also be used as a subroutine to solve problem A efficiently. When this is true, solving A cannot be harder than solving B. "Harder" means having a higher estimate of the required computational resources in a given context (e.g., higher time complexity, etc.).

We write A ≤_m B, usually with a subscript on the ≤ to indicate the type of reduction being used (m : mapping reduction, p : polynomial reduction).

The mathematical structure generated on a set of problems by the reductions of a particular type generally forms a preorder, whose equivalence classes may be used to define degrees of unsolvability and complexity classes.

Population (disambiguation)

Population may refer to:

Human population

Institut national d'études démographiques

The French Institute for Demographic Studies (INED) is a French research institute specialized in demography and population studies in general.

History

Vichy France Foundation

In 1941, Nobel Prize winner Alexis Carrel, an early proponent of eugenics and euthanasia, and a member of Jacques Doriot's French Popular Party (PPF), advocated for the creation of the Fondation Française pour l'Étude des Problèmes Humains (French Foundation for the Study of Human Problems), using connections to the Pétain cabinet. Charged with the "study, in all of its aspects, of measures aimed at safeguarding, improving and developing the French population in all of its activities", the Foundation was created by decree of the collaborationist Vichy regime in 1941, and Carrel appointed as 'regent'. The Foundation also had for some time as general secretary François Perroux.

The Foundation was behind the 16 December 1942 Act mandating the "prenuptial certificate", which required all couples seeking marriage to submit to a biological examination, to insure the "good health" of the spouses, in particular with regard to sexually transmitted diseases (STD) and "life hygiene". Carrel's institute also conceived the "scholar booklet" ("livret scolaire"), which could be used to record students' grades in French secondary schools, and thus classify and select them according to scholastic performance. Besides these eugenic activities aimed at classifying the population and improving its health, the Foundation also supported the 11 October 1946 law instituting occupational medicine, enacted by the Provisional Government of the French Republic (GPRF) after the Liberation.

Population: 2

Population: 2 is a 2012 American film directed by Gil Luna. The film was made entirely in Oregon with an all-Oregon cast and crew. It is recognized as having utilized several historic sites, one of which, the Fairview Training Center, no longer exists in its full form, having been deconstructed starting in 2011.

Plot

Set against the backdrop of a post-apocalyptic Earth, Population 2 is about Lilith who wanders the remains of civilization every day, scavenging what she can from the deserted refuse of what was once a bustling city.

Cast

External links