Programming language (APL)

What is programming language (APL)?
The programming language (APL) was first described in 1962 in a book of the same name by Kenneth E. Iverson. APL is a third generation (3GL) interactive and interpreted language that is geared towards the rigorous expression of mathematical notations by a computer in an interpretive manner. APL has a compact representation of arrays and operators that manipulate them and at the same time enable abstract problem solving. This happens from different domains and expresses algorithms that are independent of the specifics of the computer platform.

Today, APL is provided in integrated development environments (IDE) by a number of commercial and non-commercial vendors.

Before it became known as APL, the language was known simply as Iverson's language.

APL is widely used in various problem areas such as math, scientific research, visualization, engineering, robotics, and actuarial science. The language is written using the unique and non-standard APL character set. Iverson claimed that the use of this set produced a notation ability that surpassed a regular character set.

Accordingly, the performance of APL is based on the designation of common array operators, functions and their combinations with a single dedicated symbol (primitive). The result is a language that is not easy to read. However, APL has a small but passionate user base in finance, insurance, and math applications.

APL programs are interpreted rather than compiled in the APL workspace. In contrast to other languages, which are evaluated from top to bottom, APL expressions are evaluated from right to left. Originally, APL did not contain any control structures. However, modern implementations generally include a comprehensive set of control structures that enable data separation and program flow control.

APL was standardized by the American National Standards Institute (ANSI) and the International Organization for Standardization (ISO).

APL programs are best written using a dedicated keyboard with an APL-specific symbolic notation, or remapping a generic keyboard and using APL language decals to indicate APL functions.