Editing Geometric Arithmetic Parallel Processor

{{Refimprove|date=August 2007}}
In [[parallel computing]], the '''Geometric Arithmetic Parallel Processor''' ('''GAPP'''), invented by [[Poland|Polish]] [[mathematician]] [[Włodzimierz Holsztyński]] in 1981, was patented by [[Martin Marietta]]<ref>
[http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=4739474.PN.&OS=PN/4739474&RS=PN/4739474 Geometric-arithmetic parallel processor] US Patent 4,739,474, April 19, 1988
</ref> and is now owned by [[Silicon Optix]], Inc. The GAPP's [[network topology]] is a [[mesh networking|mesh]]-connected array of single-bit [[SIMD]] [[processing element]]s (PEs), where each PE can communicate with its neighbor to the north, east, south, and west. Each cell has its own memory. The space of addresses is the same for all cells. The data travels from the cell memories to the cell registers, and in the opposite direction, in parallel. Characteristically, the cell's [[arithmetic logic unit]] (ALU) (that is, its PE) in the early versions of GAPP was nothing but a [[1-bit computing|1-bit]] full-adder/subtractor, which efficiently served both the complex arithmetic as well as logical functions, and with the help of shifts it served also the geometric transformations—in short, it was doing all three types of the tasks (while other designs used three separate hardware special-purpose units instead).

The 10,000-element GAPP grew to 82,944 elements by 1992.<ref>{{cite book|author=Gilbert Kalb and Robert Moxley|title=Massively Parallel, Optical and Neural Computing in the United States|year=1992|publisher=IOS Press|isbn=9789051990973|page=20|url=https://books.google.com/books?id=7Ao4TBf4uv4C&pg=PA20}}</ref> 
In its most recent incarnation (as of 2004), the systems by Teranex utilize GAPP arrays of up to 294,912 processing elements.

In mathematics, Holsztyński is known for Holsztyński theorem. <ref>{{cite journal | last=Holsztyński|first=W. |title=Continuous mappings induced by isometries of spaces of continuous functions |journal=
Studia Mathematica | volume=26(1966)|pages=133–136}}</ref>

==References==
{{Reflist}}

[[Category:SIMD computing]]
[[Category:Digital signal processing]]

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