Ken Iverson: Difference between revisions

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Interest in naming and the English language
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(Interest in naming and the English language)
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In APL, the Iverson bracket is implied in all logical propositions, for example <syntaxhighlight lang=apl inline>4≥3</syntaxhighlight> evaluates to <syntaxhighlight lang=apl inline>1</syntaxhighlight> and <syntaxhighlight lang=apl inline>'hello'≡'world'</syntaxhighlight> evaluates to <syntaxhighlight lang=apl inline>0</syntaxhighlight>.
In APL, the Iverson bracket is implied in all logical propositions, for example <syntaxhighlight lang=apl inline>4≥3</syntaxhighlight> evaluates to <syntaxhighlight lang=apl inline>1</syntaxhighlight> and <syntaxhighlight lang=apl inline>'hello'≡'world'</syntaxhighlight> evaluates to <syntaxhighlight lang=apl inline>0</syntaxhighlight>.
== Naming things ==
Iverson's work on programming languages sometimes crossed over with his studies of the English language. [[Roger Hui]] recounts that "Ken was deeply interested in words, their use and their etymology. He indeed did read the dictionary, and kept a copy of the American Heritage Dictionary (along with other dictionaries) by his easy chair for ready reference."<ref>[[Roger Hui]]. [https://keiapl.org/rhui/remember.htm Remembering Ken Iverson]. 2004-11.</ref> He chose names for APL concepts carefully and sometimes relied on obscure meanings, for example "[[ravel]]" in the sense of unmaking a knitted fabric<ref>[[Gitte Christensen]]. [http://archive.vector.org.uk/art10002270 Ken Iverson in Denmark]. [[Vector Journal]] volume 22 issue 3.</ref> and [[nub]] meaning the essential part. In [[A Dictionary of APL]], he began to describe programming syntax in terms of English grammar, a choice that carried through to [[J]]—implementer Hui shared and encouraged Iverson's interest in English.
[[The name APL]] was chosen by [[Adin Falkoff]] and not Iverson, albeit based on his [[A Programming Language]]. However, some of Iverson's names have become accepted in mainstream mathematics or programming, such as "floor" and "ceiling" as mentioned above, and [[reduction]], which may have been named in part for how it reduces the argument's rank by one. It's possible that Iverson coined the term "bubble sort", as A Programming Language is the first publication known to use it.<ref>Owen Astrachan. [https://dl.acm.org/doi/10.1145/792548.611918 Bubble Sort: An Archaeological Algorithmic Analysis] ([https://users.cs.duke.edu/~ola/bubble/bubble.html web]). 2003-01-11.</ref><ref>[[Roger Hui]]. "APL Quotations and Anecdotes", [on bubble sort https://www.jsoftware.com/papers/APLQA.htm#bubble_sort].</ref>


== Publications ==
== Publications ==
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* [http://keiapl.org/ A Celebration of the life of Kenneth Eugene Iverson] (has many links to writings about Iverson)
* [http://keiapl.org/ A Celebration of the life of Kenneth Eugene Iverson] (has many links to writings about Iverson)


== References ==
<references/>
{{APL community}}{{DEFAULTSORT:Iverson, Ken}}[[Category:People]][[Category:Jsoftware employees]][[Category:I.P. Sharp Associates employees]][[Category:Designers]]
{{APL community}}{{DEFAULTSORT:Iverson, Ken}}[[Category:People]][[Category:Jsoftware employees]][[Category:I.P. Sharp Associates employees]][[Category:Designers]]

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