I.P. Sharp Associates
I.P. Sharp Associates (IPSA) was the vendor of SHARP APL and a major contributor to the APL community and the flat array model in the 1970s and 1980s. Like its U.S. counterpart STSC, the Canadian IPSA served as a center of APL research, hiring notable interpreter designers and implementers from IBM and starting the careers of many other notable implementors. It also sponsored the IPSA conferences.
IPSA was founded in 1964 by an eight-person team including president Ian Sharp and Roger Moore. Initially a contractor for IBM System/360 programming, the company quickly became involved with APL, with Moore helping to implement APL\360 beginning in 1966. In the next few years, IPSA worked with STSC to improve APL\360. The resulting interpreter, called APL*PLUS, was offered by both companies as part of a time-sharing service: IPSA offered this service in Canada while STSC offered it in the United States.
Around 1976 IPSA renamed their implementation SHARP APL, and the language began to diverge from STSC's, which retained the name APL*PLUS. The divide widened in 1981, when SHARP APL introduced boxes to handle nested data within the flat array model, while STSC released NARS, an experimental APL implementation whose nested array model would be used in later versions of APL*PLUS. During this period IPSA also began to sell SHARP APL as a stand-alone software product (beginning around 1979), in anticipation of the decline of time-sharing systems in favor of on-premise datacenters. It offered several conferences, or user meetings, beginning in 1978.
In 1984, IPSA released SHARP APL/PC, a personal computer version of SHARP APL, which now competed with IBM's APL2 in addition to APL*PLUS. Soon it would also release SAX, or Sharp APL for Unix. By this time the rapid reduction in time-sharing revenue had caused the company's profitability to decline; it was purchased by Reuters Group in 1987 and president Ian Sharp retired in 1989. The company was finally closed in 2005.
IPSA's roster of APL designers and implementors included cofounder Roger Moore, former IBM employees Ken Iverson and Dick Lathwell, and new implementors Roger Hui, Eric Iverson, Arthur Whitney, and Bob Bernecky. After it was acquired in 1987 by Reuters, many IPSA employees went on to create other commercial efforts: Hui joined both Iversons to develop J as part of Jsoftware, Whitney designed A+ and later founded Kx Systems and then Shakti to sell K, and Bernecky created the APEX APL compiler. Two other employees, Morten Kromberg and Gitte Christensen, founded the APL-based company Insight Systems, and later took over management of Dyalog Ltd.
In 1993 the company Soliton Incorporated was formed by a group of former I.P. Sharp employees and bought IPSA's APL division from Reuters. Soliton offered the SAX programming language until about 2017.
|APL development |
|Interface||Session ∙ Typing glyphs (on Linux) ∙ Fonts ∙ Text editors|
|Publications||Introductions ∙ Learning resources ∙ Simple examples ∙ Advanced examples ∙ Mnemonics ∙ Standards ∙ A Dictionary of APL ∙ Case studies ∙ Documentation suites ∙ Books ∙ Papers ∙ Videos ∙ Periodicals ∙ Terminology (Chinese, German) ∙ Neural networks ∙ Error trapping with Dyalog APL (in forms)|
|Sharing code||Backwards compatibility ∙ APLcart ∙ APLTree ∙ APL-Cation ∙ Dfns workspace ∙ Tatin|
|Implementation||Developers (APL2000, Dyalog, GNU APL community, IBM, IPSA, STSC) ∙ Resources ∙ Open-source ∙ Magic function ∙ Performance ∙ APL hardware|