In mathematics, an operator is a function, usually of a special kind depending on the topic. For instance, in linear algebra an "operator" is a linear operator. In analysis an "operator" may be a differential operator, generalizing the ordinary derivative, or an integral operator, generalizing ordinary integration. Often, an "operator" is a function that acts on functions to produce other functions; or it may be a generalization of such a function, as in linear algebra, where some of the terminology reflects the origin of the subject in operations on the functions that are solutions of differential equations. One often thinks of an operator as dynamic, changing something into something else, whence the name; but this is only a way of thinking and not a formal definition.

An operator name or operator symbol is a notation that denotes a particular operator. When there is no danger of confusion, an operator name or operator symbol may be referred to more briefly as an "operator". Strictly speaking, however, the operator is a mathematical object and not the syntactic entity that denotes it. The reason for identifying it with its notation is that there are some operators that have come to have standard notations.

An example of an operator, specifically a differential operator, is the derivative itself. The corresponding operator name D, when placed before a differentiable function f, indicates that the function is to be differentiated with respect to the variable.

More on [ Operator ]

NYT > Travel

Frugal Traveler | The Grand Tour: Shipyards to Sheratons in Gdansk
Wed, 23 Jul 2008 20:58:27 -0000
With readers as his guide, the Frugal Traveler soaks up the history and culture of this Baltic Sea town on the Polish Riviera.
Surfacing | Soi Arab, Bangkok: A Crossroads of Two Cultures
Thu, 17 Jul 2008 23:34:07 -0000
The colorful pedestrian alleyway, lined with shisha bars and Saudi restaurants, teems with an energy that is more Middle Eastern than Thai.
Next Stop | Mexico: Move Over Oaxaca, Arty Michoacán Is Calling
Fri, 18 Jul 2008 17:50:09 -0000
A new stop on the Mexican crafts trail, the region is attracting more tourists and collectors with its colorful ceramics and glittering copper works.

Forbes.com: Travel News

Eight Sensational Scuba-Diving Trips
Rebecca Ruiz Tue, 22 Jul 2008 14:00:00 -0000
Strap on an air tank and visit another world.
Guilt-Free Luxury Travel
Rebecca Ruiz Thu, 17 Jul 2008 10:00:00 -0000
You don't have to feel guilty about spending thousands on a luxury vacation--especially if most of the money goes to charity.
Luxury Travel Bargains Close To Home
Courtney Myers Thu, 17 Jul 2008 15:00:00 -0000
High-end hotels and resorts are dropping rates and offering special deals to keep their rooms full this summer.

Subscribe to Travel RSS feed