Category

Category, plural categories, may refer to:

Philosophy and general uses

Mathematics

Linguistics

Lusternik–Schnirelmann category

In mathematics, the Lyusternik–Schnirelmann category (or, Lusternik–Schnirelmann category, LS-category) of a topological space is the homotopical invariant defined to be the smallest integer number such that there is an open covering of with the property that each inclusion map is nullhomotopic. For example, if is the circle, this takes the value two.

Sometimes a different normalization of the invariant is adopted, which is one less than the definition above Such a normalization has been adopted in the definitive monograph by Cornea, Lupton, Oprea, and Tanré (see below).

In general it is not easy to compute this invariant, which was initially introduced by Lazar Lyusternik and Lev Schnirelmann in connection with variational problems. It has a close connection with algebraic topology, in particular cup-length. In the modern normalization, the cup-length is a lower bound for LS category.

It was, as originally defined for the case of X a manifold, the lower bound for the number of critical points that a real-valued function on X could possess (this should be compared with the result in Morse theory that shows that the sum of the Betti numbers is a lower bound for the number of critical points of a Morse function).

Grammatical category

A grammatical category is a property of items within the grammar of a language; it has a number of possible values (sometimes called grammemes), which are normally mutually exclusive within a given category. Examples of frequently encountered grammatical categories include tense (which may take values such as present, past, etc.), number (with values such as singular, plural, and sometimes dual), and gender (with values such as masculine, feminine and neuter).

Although terminology is not always consistent, a distinction should be made between these grammatical categories (tense, number, etc.) and lexical categories, which are closely synonymous with the traditional parts of speech (noun, verb, adjective, etc.), or more generally syntactic categories. Grammatical categories are also referred to as (grammatical) features.

The name given to a grammatical category (as an uncountable noun) is generally also used (as a countable noun) to denote any of the possible values for that category. For example, the values available in a given language for the category "tense" are called "tenses", the values available for the category "gender" are called "genders", and so on.

Flour (disambiguation)

Flour is a common food ingredient made from wheat, rice, or other starchy sources.

Flour may also refer to:

See also

Flour (band)

Flour is an American band. Flour is the nickname of Minneapolis musician Pete Conway who wrote songs and played bass guitar in the bands Rifle Sport and Breaking Circus until the mid-1980s. He released four solo albums on Touch and Go Records from 1988 to 1994 on which he plays most of the instruments himself. Flour toured as a live band twice with a lineup that featured ex-Big Black guitarist Steve Albini on bass and former Breaking Circus percussionist Todd Trainer on drums before they went on to form the band Shellac. Flour's solo recordings feature the drum machine sound characteristic of Big Black and toyed with by many other independent rock bands in the Midwest during that time period. Flour's third solo album Machinery Hill was described by Allmusic's Richard Foss as "an oddball masterpiece of grinding guitar, fluid bass, hammering drums, and very creative ideas".

In the mid-1990s, Conway was part of an all-bass trio, called Brits Out of America, along with Dana Cochrane of Mickey Finn, Amy Larson of Strumpet, and Ben Ivascu of Polica, STNNNG, Marijuana Deathsquads, etc.