Rope (data structure)

In computer programming, a rope, or cord, is a data structure composed of smaller strings that is used for efficiently storing and manipulating a very long string. For example, a text editing program may use a rope to represent the text being edited, so that operations such as insertion, deletion, and random access can be done efficiently.

Description

A rope is a binary tree having leaf nodes that contain a short string. Each node has a weight value equal to the length of its string plus the sum of all leaf nodes' weight in its left subtree, namely the weight of a node is the total string length in its left subtree for a non-leaf node, or the string length of itself for a leaf node. Thus a node with two children divides the whole string into two parts: the left subtree stores the first part of the string. The right subtree stores the second part and its weight is the sum of the left child's weight and the length of its contained string.

The binary tree can be seen as several levels of nodes. The bottom level contains all the nodes that contain a string. Higher levels have fewer and fewer nodes. The top level consists of a single "root" node. The rope is built by putting the nodes with short strings in the bottom level, then attaching a random half of the nodes to parent nodes in the next level.

Rope (unit)

A rope may refer to any of several units of measurement initially determined or formed by ropes or knotted cords.

Length

The Greco-Roman schoenus, supposedly based on an Egyptian unit derived from a wound reed measuring rope, may also be given in translation as a "rope". According to Strabo, it varied in length between 30 to 120 stadia (roughly 5 to 20 km) depending on local custom.

The Byzantine equivalent, the schoinion or "little rope", varied between 60 to 72 Greek feet depending upon the location.

The Thai sen of 20 Thai fathoms or 40 m also means and is translated "rope".

The Somerset rope was a former English unit used in drainage and hedging. It was 20 feet (now precisely 6.096 m).

Area

The Romans used the schoenus as an alternate name for the half-jugerum formed by a square with sides of 120 Roman feet.

In Somerset, the rope could also double as a measure of area equivalent to 20 feet by 1 foot. Walls in Somerset were formerly sold "per rope" of 20 sq ft.

Garlic

In medieval English units, the rope of garlic was a set unit of 15 heads of garlic. 15 such ropes made up the "hundred" of garlic.

Rope (rhythmic gymnastics)

Rope (rhythmic gymnastics) may be made of hemp or a synthetic material which retains the qualities of lightness and suppleness. Its length is in proportion to the size of the gymnast. The rope should, when held down by the feet, reach both of the gymnasts' armpits. One or two knots at each end are for keeping hold of the rope while doing the routine. At the ends (to the exclusion of all other parts of the rope) an anti-slip material, either coloured or neutral may cover a maximum of 10 cm (3.94 in). The rope must be coloured, either all or partially. It may be either of a uniform diameter or be progressively thicker in the center provided that this thickening is of the same material as the rope.

The fundamental requirements of a rope routine include leaps and skipping. Other elements include swings, throws, circles, rotations and figures of eight.

Magnet

A magnet (from Greek μαγνήτις λίθος magnḗtis líthos, "Magnesian stone") is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, and attracts or repels other magnets.

A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. An everyday example is a refrigerator magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic (or ferrimagnetic). These include iron, nickel, cobalt, some alloys of rare earth metals, and some naturally occurring minerals such as lodestone. Although ferromagnetic (and ferrimagnetic) materials are the only ones attracted to a magnet strongly enough to be commonly considered magnetic, all other substances respond weakly to a magnetic field, by one of several other types of magnetism.

Magnet Kitchens

Magnet is a British kitchen retailer operating in over 200 locations across the UK supplying products under the Magnet and Magnet Trade brands. The company has over 2,000 employees and its headquarters are in Darlington, County Durham. Magnet was listed on the London Stock Exchange and was once a constituent of the FTSE 100 Index but is now part of Nobia UK, a division of the Nobia group which is listed on the Swedish Stock Exchange.' The Nobia division also includes brands such as Gower, Hygena and Norema.

History

Formation and Early Years

Magnet was established in Bingley, West Yorkshire in 1918 by Tom Duxbury. Legend has it that Duxbury traded his horse for a firelighting company and named his new company Magnet after the horse. During the 1920s Magnet pioneered the mass production of joinery, door and window products and soon began supplying joinery components for major construction projects. New operations were opened in Keighley, Grays and Knaresborough to satisfy demand for the growing business.

Magnet (magazine)

Magnet is a music magazine which generally focuses on alternative, independent, or out-of-the-mainstream bands.

History

The magazine is published four times a year, and is independently owned and edited by Eric T. Miller. Music magazines with a similar focus in the 1990s era included Option, Raygun, and Alternative Press. The first issue of Magnet came out in mid-1993. Examples of cover stars over the years include Yo La Tengo (1993, 2000), The Afghan Whigs (1994), Spacemen 3 (1997), Shudder To Think (1997), Tortoise/ Swervedriver (1998), Sonic Youth (1998), Sunny Day Real Estate (1998), Ween (2000), Ride (2002), Interpol (2003), Hüsker Dü (2005), and Cat Power (2007).

The magazine's content tends to focus on up-and-coming indie bands and expositions of various music scenes. Examples include long pieces on the Denton, TX psychedelic rock scene (1997), the New York City "Illbient" scene (1997), the history of power pop (2002), the Cleveland avant-punk scene of the 1970s, the Minneapolis college-rock scene of the '80s (2005), the California "Paisley Underground" bands of the '80s (2001), and the resurgence of the Shoegaze movement (2002). Also common is the "artists within a construct" theme -- e.g., the "Eccentrics And Dreamers" issue (2003) featuring various "outsider" artists.