Field (agriculture)

In agriculture, a field is an area of land, enclosed or otherwise, used for agricultural purposes such as cultivating crops or as a paddock or other enclosure for livestock. A field may also be an area left to lie fallow or as arable land.

Many farms have a field border, usually composed of a strip of shrubs and vegetation, used to provide food and cover necessary for the survival of wildlife. It has been found that these borders may lead to an increased variety of animals and plants in the area, but also in some cases a decreased yield of crops.

Language

In Australian and New Zealand English, any agricultural field may be called a paddock. If stock are grazed there, the space may be called a run, e.g. sheep run; cattle run.

Image gallery

A green field or paddock with Hereford cattle

A green field or paddock with Hereford cattle

A summer field

A summer field

Spring fields with trees, Majorca, Spain, 2004

Spring fields with trees, Majorca, Spain, 2004

Field (computer science)

In computer science, data that has several parts, known as a record, can be divided into fields. Relational databases arrange data as sets of database records, also called rows. Each record consists of several fields; the fields of all records form the columns.

In object-oriented programming, field (also called data member or member variable) is the data encapsulated within a class or object. In the case of a regular field (also called instance variable), for each instance of the object there is an instance variable: for example, an Employee class has a Name field and there is one distinct name per employee. A static field (also called class variable) is one variable, which is shared by all instances.

Fixed length

Fields that contain a fixed number of bits are known as fixed length fields. A four byte field for example may contain a 31 bit binary integer plus a sign bit (32 bits in all). A 30 byte name field may contain a persons name typically padded with blanks at the end. The disadvantage of using fixed length fields is that some part of the field may be wasted but space is still required for the maximum length case. Also, where fields are omitted, padding for the missing fields is still required to maintain fixed start positions within a record for instance.

Field (mathematics)

In mathematics, a field is one of the fundamental algebraic structures used in abstract algebra. It is a nonzero commutative division ring, or equivalently a ring whose nonzero elements form an abelian group under multiplication. As such it is an algebraic structure with notions of addition, subtraction, multiplication, and division satisfying the appropriate abelian group equations and distributive law. The most commonly used fields are the field of real numbers, the field of complex numbers, and the field of rational numbers, but there are also finite fields, algebraic function fields, algebraic number fields, p-adic fields, and so forth.

Any field may be used as the scalars for a vector space, which is the standard general context for linear algebra. The theory of field extensions (including Galois theory) involves the roots of polynomials with coefficients in a field; among other results, this theory leads to impossibility proofs for the classical problems of angle trisection and squaring the circle with a compass and straightedge, as well as a proof of the Abel–Ruffini theorem on the algebraic insolubility of quintic equations. In modern mathematics, the theory of fields (or field theory) plays an essential role in number theory and algebraic geometry.

Plasma

Plasma or plasm may refer to:

Biology

Computing

Media and entertainment

KDE

KDE (/ˌkeɪdiːˈiː/) is an international free software community producing free and libre software like Plasma Desktop, KDE Frameworks and many cross-platform applications designed to run on modern Unix-like and Microsoft Windows systems. The Plasma Desktop is a desktop environment provided as the default work environment on many Linux distributions, such as openSUSE, Mageia, Kubuntu, Manjaro Linux and also the default desktop environment on PC-BSD, a BSD operating system.

The goal of the community is to develop free software solutions and applications for the daily needs of an end-user, as well as providing tools and documentation for developers to write such software. In this regard, the resources provided by KDE make it a central development hub and home for many popular applications and projects like Calligra Suite, Krita, digiKam, and many others.

History

Origins

K Desktop Environment (KDE) was founded in 1996 by Matthias Ettrich, who was then a student at the Eberhard Karls University of Tübingen. At the time, he was troubled by certain aspects of the Unix desktop. Among his concerns was that none of the applications looked, felt, or worked alike. He proposed the creation of not merely a set of applications but a desktop environment in which users could expect things to look, feel, and work consistently. He also wanted to make this desktop easy to use; one of his complaints about desktop applications of the time was that it is too complicated for end user. His initial Usenet post spurred a lot of interest, and the KDE project was born.

KDE Plasma 4

KDE Plasma 4, subsequently renamed from KDE Plasma Workspaces, is the umbrella term for the fourth generation graphical environments provided by KDE. It comprehended of three workspaces, each targeting a certain platform: Plasma Desktop for traditional desktop PCs and notebooks, Plasma Netbook for netbooks, and Plasma Active for tablet PCs and similar devices.

KDE Plasma 4 was released as part of KDE Software Compilation 4 and replaced Kicker, KDesktop, and SuperKaramba, which formed the Desktop in earlier KDE releases. They are bundled as the default environment with a number of free software operating systems, such as Chakra,Kubuntu,Mageia (DVD version),openSUSE, or PC-BSD.

With the release of KDE SC 4.11 on 14 August 2013 KDE Plasma 4 was put into "feature freeze" and turned into an long-time stable package until August 2015. On 15 July 2014 KDE Plasma 4’s successor, KDE Plasma 5, was released.

Features

Plasma features containments, essentially an applet that contains other applets. Two examples of containments are the desktop background and the taskbar. A containment can be anything the developer wants: an image (either raster graphics or an SVG image), animation, or even OpenGL. Images are most commonly used, but with Plasma the user could set any applet as the desktop background without losing functionality of the applet. This also allows for applets to be dragged between the desktop and the taskbar (two separate containments), and have a separate visualization for the more confined taskbar.