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(science and technology)
Relating to the simplest or most significant form of a general function, equation, statement, rule, or expression.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


(Historically, "according to religious law")

1. <mathematics> A standard way of writing a formula. Two formulas such as 9 + x and x + 9 are said to be equivalent because they mean the same thing, but the second one is in "canonical form" because it is written in the usual way, with the highest power of x first. Usually there are fixed rules you can use to decide whether something is in canonical form. Things in canonical form are easier to compare.

2. <jargon> The usual or standard state or manner of something. The term acquired this meaning in computer-science culture largely through its prominence in Alonzo Church's work in computation theory and mathematical logic (see Knights of the Lambda-Calculus).

Compare vanilla.

This word has an interesting history. Non-technical academics do not use the adjective "canonical" in any of the senses defined above with any regularity; they do however use the nouns "canon" and "canonicity" (not "canonicalness"* or "canonicality"*). The "canon" of a given author is the complete body of authentic works by that author (this usage is familiar to Sherlock Holmes fans as well as to literary scholars). "The canon" is the body of works in a given field (e.g. works of literature, or of art, or of music) deemed worthwhile for students to study and for scholars to investigate.

The word "canon" derives ultimately from the Greek "kanon" (akin to the English "cane") referring to a reed. Reeds were used for measurement, and in Latin and later Greek the word "canon" meant a rule or a standard. The establishment of a canon of scriptures within Christianity was meant to define a standard or a rule for the religion. The above non-technical academic usages stem from this instance of a defined and accepted body of work. Alongside this usage was the promulgation of "canons" ("rules") for the government of the Catholic Church. The usages relating to religious law derive from this use of the Latin "canon". It may also be related to arabic "qanun" (law).

Hackers invest this term with a playfulness that makes an ironic contrast with its historical meaning. A true story: One Bob Sjoberg, new at the MIT AI Lab, expressed some annoyance at the incessant use of jargon. Over his loud objections, GLS and RMS made a point of using as much of it as possible in his presence, and eventually it began to sink in. Finally, in one conversation, he used the word "canonical" in jargon-like fashion without thinking. Steele: "Aha! We've finally got you talking jargon too!" Stallman: "What did he say?" Steele: "Bob just used "canonical" in the canonical way."

Of course, canonicality depends on context, but it is implicitly defined as the way *hackers* normally expect things to be. Thus, a hacker may claim with a straight face that "according to religious law" is *not* the canonical meaning of "canonical".
This article is provided by FOLDOC - Free Online Dictionary of Computing (


The standard or authoritative method. The term comes from "canon," which is the law or rules of the church. See canonical name and canonical synthesis.
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References in periodicals archive ?
(b) If L has left coprime factorization [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], then L can be stabilized by canonical controller ([MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII]) if and only if [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] is invertible in S.
Table 1-Canonical weights, canonical coefficients, and descriptive statistics for dependent variables of microhabitat with age of black phoebes (Sayornis nigricans) as an independent variable.
Canonical is a private company owned by South African Mark Shuttleworth which supports Ubuntu.
The canonical coronation rites will be held on March 25, 2020 at the National Shrine of Our Lady of Sorrows, which houses the Marian icon.
When it comes to racism and sexism, in this context, the question is less whether we should read canonical texts in our respective fields but how we should read them.
This is because log canonical singularities are known to be Du Bois (see [14]).
"We are delighted to welcome Storage Made Easy to the Juju ecosystem," said Arturo Suarez, Program Director at Canonical. "SME's Enterprise File Fabric adds a set of outstanding features to our catalogue of storage solutions, doubling down on our commitment to offer our customers flexibility, security and the economics to run their applications at scale across different platforms."
Canonical variables are calculated from the ORCCA and ORKCCA algorithms for the different values of regularization parameters.
Like all multivariate analysis techniques, the canonical correlation analysis is potentially an important technique for the analysis of large data sets since a total ofpxq correlations in the two data sets are reduced to minimum of (p, q) canonical correlations representing several dimensions of the relationship.
By using the standardized canonical coefficients, the contribution of response variables can be determined in each contrast (RENCHER, 2002).
(NYSE: QTS) and Canonical has unveiled a private, fully managed openstack cloud solution to manage private cloud offerings, the companies said.
The canonical inquiry--an important next step in the canonization process --will result in a report placing Day's life in historical context and reviewing her unpublished writings.