Swap

Swap or SWAP may refer to:

Finance

Science and technology

Other

See also

Swap (finance)

A swap is a derivative in which two counterparties exchange cash flows of one party's financial instrument for those of the other party's financial instrument. The benefits in question depend on the type of financial instruments involved. For example, in the case of a swap involving two bonds, the benefits in question can be the periodic interest (coupon) payments associated with such bonds. Specifically, two counterparties agree to exchange one stream of cash flows against another stream. These streams are called the legs of the swap. The swap agreement defines the dates when the cash flows are to be paid and the way they are accrued and calculated. Usually at the time when the contract is initiated, at least one of these series of cash flows is determined by an uncertain variable such as a floating interest rate, foreign exchange rate, equity price, or commodity price.

The cash flows are calculated over a notional principal amount. Contrary to a future, a forward or an option, the notional amount is usually not exchanged between counterparties. Consequently, swaps can be in cash or collateral.

Swap (computer science)

In computer programming, the act of swapping two variables refers to mutually exchanging the values of the variables. Usually, this is done with the data in memory. For example, in a program, two variables may be defined thus (in pseudocode):

(In many programming languages where the swap function is built-in; in C++, overloads are provided allowing std::swap to swap some large structures in O(1) time.) After swap() is performed, x will contain the value 0 and y will contain 1; their values have been exchanged. Of course, this operation may be generalized to other types of values, such as strings, aggregated data types and comparison sorts, utilize swaps to change the positions of data.

Using a temporary variable

The simplest and probably most widely used method to swap two variables is to use a third temporary variable:

While this is conceptually simple and in many cases the only convenient way to swap two variables, it uses extra memory. Although this should not be a problem in most applications, the sizes of the values being swapped may be huge (which means the temporary variable may occupy a lot of memory as well), or the swap operation may need to be performed many times, as in sorting algorithms.