extremal


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ex·trem·al

 (ĭk-strē′məl)
adj.
1. Mathematics Of or relating to maximal or minimal values or degrees of inclusiveness.
2. Having or characterized by extreme properties or conditions: extremal black holes.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

extremal

(ɪkˈstriːməl)
n
(Logic) maths logic the clause in a recursive definition that specifies that no items other than those generated by the stated rules fall within the definition, as in 1 is an integer, if n is an integer so is n+1, and nothing else is
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Let [l.sub.n] be an extremal rational curve whose numerical class [[l.sub.n]] spans the extremal ray [R.sub.n], i.e., [R.sub.n] = [R.sub.[greater than or equal to]0] [[l.sub.n]].
They use this notion to classify *-homomorphisms from separable, unital, nuclear C*-algebras into ultrapowers of simple, unital, nuclear -stable C*-algebras with compact extremal trace space up to 2-colored equivalence by their behavior of traces.
If there is only one solution [r.sub.0], then B is empty and the black hole is called extremal.
The extremal function for conic domain [[OMEGA].sub.B] is the mapping [p.sub.[beta]](z) with [p.sub.[beta]](0) = 1 and [p'.sub.[beta]](0) > 0 and is defined by
Suppose A;B [member of] WCC (X): Then A; B are weakly compact, convex subsets of X: Since addition and scalar multiplication are continuous operations on (X; [T.sub.w]) ; we have A + B; [alpha]A are weakly compact, convex subsets of X; i:e:; A + B; [alpha]A [member of] WCC (X): Thus we may define, algebraic line segments, convex sets, extremal subsets and extreme points on the hyperspace WCC (X) analogous to their counterparts on the underlying space X:
Termination of extremal rays of divisorial type for the power of etale endomorphisms ...
Their topics include extremal problems in the symmetrized bidisc, purely unbalanced and exceptional datums, geodesics and sets with the norm-preserving extension property, proof of the main theorem, and applications to the theory of spectral sets.
That is, through the phenomenological reduction to itself--in the history of its structure--self-consciousness removes all the extremes and extremal positions from the field of negation whereof it elicits and where it acts.
The sample reference maps consist of strong text map and non-text map based on a combination of maximally stable extremal regions (MSERs) and saliency map.