Trimming (computer programming)

In computer programming, trimming (trim) or stripping (strip) is a string manipulation in which leading and trailing whitespace is removed from a string.

For example, the string (enclosed by apostrophes)

would be changed, after trimming, to

Variants

Definition of whitespace

The characters which are considered whitespace varies between programming languages and implementations. For example, C traditionally only counts space, tab, line feed, and carriage return characters, while languages which support Unicode typically include all Unicode space characters. Some implementations also include ASCII control codes (non-printing characters) along with whitespace characters.

Java's trim method considers ASCII spaces and control codes as whitespace, contrasting with the Java isWhitespace() method, which recognizes all Unicode space characters.

Delphi's Trim function considers characters U+0000 (NULL) through U+0020 (SPACE) to be whitespace.

Usage

Following are examples of trimming a string using several programming languages. All of the implementations shown return a new string and do not alter the original variable.

Trim (computing)

A Trim command (known as TRIM in the ATA command set, and UNMAP in the SCSI command set) allows an operating system to inform a solid-state drive (SSD) which blocks of data are no longer considered in use and can be wiped internally.

Trim was introduced soon after SSDs were introduced. Because low-level operation of SSDs differs significantly from hard drives, the typical way in which operating systems handle operations like deletes and formats resulted in unanticipated progressive performance degradation of write operations on SSDs. Trimming enables the SSD to handle garbage collection overhead, which would otherwise significantly slow down future write operations to the involved blocks, in advance.

Although tools to "reset" some drives to a fresh state were already available before the introduction of trimming, they also delete all data on the drive, which makes them impractical to use for ongoing optimization. By 2014 many SSDs had internal idle/background garbage collection mechanisms that work independently of trimming; although this successfully maintains their performance even under operating systems that do not support Trim, it has the associated drawbacks of increased write amplification and wear of the flash cells.

Trim (sewing)

Trim or trimming in clothing and home decorating is applied ornament, such as gimp, passementerie, ribbon, ruffles, or, as a verb, to apply such ornament.

Before the industrial revolution, all trim was made and applied by hand, thus making heavily trimmed furnishings and garments expensive and high-status. Machine-woven trims and sewing machines put these dense trimmings within the reach of even modest dressmakers and home sewers, and an abundance of trimming is a characteristic of mid-Victorian fashion. As a predictable reaction, high fashion came to emphasize exquisiteness of cut and construction over denseness of trimming, and applied trim became a signifier of mass-produced clothing by the 1930s. The iconic braid and gold button trim of the Chanel suit are a notable survival of trim in high fashion.

In home decorating, the 1980s and 1990s saw a fashion for dense, elaborately layered trimmings on upholstered furniture and drapery.

Today, most trimmings are commercially manufactured. Scalamandré is known for elaborate trim for home furnishings, and Wrights is a leading manufacturer of trim for home sewing and crafts. Trims are used generally to enhance the beauty of the garments. It attracts buyers. Appropriate use of it creates more value of the product.

Fen

A fen is one of the main types of wetland, the others being grassy marshes, forested swamps, and peaty bogs. Along with bogs, fens are a kind of mire. Fens are usually fed by mineral-rich surface water or groundwater. They are characterised by their water chemistry, which is pH neutral or alkaline, with relatively high dissolved mineral levels but few other plant nutrients. They are usually dominated by grasses and sedges, and typically have brown mosses in general including Scorpidium or Drepanocladus. Fens frequently have a high diversity of other plant species including carnivorous plants such as Pinguicula. They may also occur along large lakes and rivers where seasonal changes in water level maintain wet soils with few woody plants. The distribution of individual species of fen plants is often closely connected to water regimes and nutrient concentrations.

Fens have a characteristic set of plant species, which sometimes provide the best indicators of environmental conditions. For example, fen indicator species in New York State include Carex flava, Cladium mariscoides, Potentilla fruticosa, Pogonia ophioglossoides and Parnassia glauca.

Car (surname)

Car is a surname. Notable people with the surname include:

CAR-301,060

CAR-301,060 (also known as cis-2-Methyl-3-quinuclidinylphenylcyclopentylglycolate or just by its code number 301060) is a potent and long lasting anticholinergic deliriant drug, related to the chemical warfare agent 3-Quinuclidinyl benzilate (QNB). It was developed under contract to Edgewood Arsenal during the 1960s as part of the US military chemical weapons program, during research to improve upon the properties of earlier agents such as QNB.

CAR-301,060 was found to be slightly less potent than QNB, and with around the same duration of action, but with a very high central to peripheral effects ratio.

See also

References