Papers

Kenneth E. Iverson. The Description of Sequential Processes. B&W scan. by Paul McJones — last modified 2008-05-22 12:14

Kenneth E. Iverson. The Description of Sequential Processes. Preprint of a paper presented at 4th London Conference on Information Theory, August 1960. Ditto machine copy, two colors. B&W scan.

Kenneth E. Iverson. The Description of Sequential Processes. Color scan. by Paul McJones — last modified 2008-05-22 12:14

Kenneth E. Iverson. The Description of Sequential Processes. Preprint of a paper presented at 4th London Conference on Information Theory, August 1960. Ditto machine copy, two colors. Color scan.

APL in Exposition by Lee Courtney — last modified 2008-08-21 19:23

Ken Iverson - IBM Philadelphia Scientific Center. The following pages illustrate the use of APL for exposition in the teaching of various topics. The first section presents the characteristics of the language, and each of the succeeding sections illustrates its use in the presentation of material in some one discipline.

AN INTRODUCTION TO APL FOR SCIENTISTS AND ENGINEERS by Lee Courtney — last modified 2008-08-21 19:23

Ken Iverson - IBM Philadelphia Scientific Center. This is an introduction to APL addressed to the scientist or engineer and designed to exploit any previous acquaintance with the very similar notation of vector algebra.

INTRODUCING APL TO TEACHERS by Lee Courtney — last modified 2008-08-21 19:23

Ken Iverson - Philadelphia Scientific Center. This paper presents such an introduction to APL for teachers of high school mathematics.

THE USE OF APL IN TEACHING by Lee Courtney — last modified 2008-08-21 19:23

The present work consists of a summary of eight lectures delivered by Dr. Kenneth Iverson at Queen's University on March 21 and 22, 1968, to an enthusiastic audience of professors and High School teachers from Ontario and Quebec.

APLSV User's Manual by Lee Courtney — last modified 2008-08-21 19:23

A. D. Falkoff, K. E. Iverson - IBM Philadelphia Scientific Center. The major difference is the addition of a shared variable facility which provides simple and effective channels of communication between programs running at different terminals, and also forms a basis for managing files and high speed input and output from an APL terminal. The facility itself is managed by a group of dynamically executable system functions provided for this purpose.

Collected Whizbangs by Lee Courtney — last modified 2008-08-21 19:23

Roy A. Sykes - Scientific Time Sharing Coporation. In December 1974 Scientific Time Sharing Corporation held a seminar for its APL*PLUS Service Representatives. One outcome of that seminar was a "wish list" of goodies these marketing folks would like to have. On that list, they expressed a desire for some sort of "APL Whizbang" -- a column describing neat programming tricks that would illustrate some powerful, but perhaps not obvious, features of the language.

An Introduction to APL by Lee Courtney — last modified 2008-08-21 19:23

Dennis Taylor - Xerox Data Systems. Xerox Data Systems introduction to APL on the Sigma-6/7/9 series of mainframes.

CRMS APL PROCESSOR REFERENCE MANUAL by Lee Courtney — last modified 2008-08-21 19:23

Paul McJones - University of California Berkeley. One of the major goals of the new CRMS computer system is to provide efficient, time-shared APL. 'The system contains two processors with common main (core) and auxiliary (disk) memories, as well as controllers for a variety of peripheral devices. One processor (the primary subject of this document) is specially tailored for the execution of APL programs. The other processor is optimized for executing programs in the SIMPLE programming language and is described elsewhere.

Compiling APL: The Yorktown APL Translator by Lee Courtney — last modified 2008-08-21 19:23

Graham C. Driscoll, Jr and Donald L. Orth - IBM Thomas J. Watson Research Center. The Yorktown APL Translator (YAT) permits functions written in APL to be compiled using an existing compiler for part of the process it also creates tables that allow the APL2 Release 2 interpreter to call the compiled code. The code can also be called from a Fortran main routine. This paper outlines the history of APL compilation, the motivation for producing YAT, the design choices that were made, and the manner of implementation. Sample APL functions and their translations are shown, and the time required to interpret these functions is compared with the time required to execute the compiled code. Possible furtherwork is discussed.

An APL Machine by Lee Courtney — last modified 2008-08-21 19:23

Philip S. Abrams - Stanford Linear Accelerator Center. This dissertation proposes a design for a machine structure which is appropriate for APL and which evaluates programs in this language efficiently.

APLSV Operations Guide IBM SH20-1461-0 by Chris Langreiter — last modified 2010-05-04 15:50

"This manual contains the information necessary to install, operate and maintain APLSV and TSIO. TSIO is an IBM-supplied auxiliary processor which provides access to Operating System datasets from APLSV terminals. [...]" (Contributed by Luis Bengochea)

A SOFTWARE HIGH PERFORMANCE APL INTERPRETER by Lee Courtney — last modified 2011-02-26 20:08

The design of a high performance APL system is presented along with an evaluation of the performance improvement measured on a partial implementation. The system contains a compiler which translates APL into the instructions of a virtual APL machine. Numerous special techniques suitable for optimized interpretation of this virtuaI machine entirely in software on a System 370 are described. The overhead for executing APL programs has been reduced by a factor ranging between 5 and 10 when compared to cciverrti oneI interpretive systems. One realistic example is analyzed in depth; there the compiled version runs 6 to 8 times faster than APLSV (Version 1.2) .

The APL IDIOM LIST by Lee Courtney — last modified 2011-02-25 18:10

 

ALGORITHMS FOR ARTIFICIAL INTELLIGENCE IN APL2 by Lee Courtney — last modified 2011-02-26 20:08

Many great advances in science and mathematics were preceded by notational improvements. While a given algorithm can be implemented in any general purpose programming language, discovery of algorithms is heavily influenced by the notation used to investigate them. APL2 conceptualy applies functions in parallel to arrays of data and so is a natural notation in which to investigate parallel algorithims. No claim is made that APL2 is an advance in notation that will precede a breakthrough in Artificial Intelligence but it is a new notation that allows a new view of the problems in AI and their solutions. APL2 can be used all problems practitionally programmed in LISP, and is a possible implementation language for PROLOG-like languages. This paper introduces a subset of the APL2 notation and explores how it can be applied to Artificial Intelligence.

My Favorite Idiom by Lee Courtney — last modified 2011-02-26 20:41

This paper discusses APL idioms: what they are, which ones are commonly recognized by people, which ones can be recognized by the APL2 interpreter, and which ones are recognized by the APL2 interpreter. Included is a discussion of why idioms are so valuable.

Idioms and Problem Solving Techniques in APL2 by Lee Courtney — last modified 2011-02-26 20:48

Idioms form an intermediate language, higher level than individual primitives but lower level than subfunctions. When a common task arises (such as sorting a vector of strings), and the programmer knows the idiom that performs that task, the task is immediately solved using the idiom. An order of magnitude gain in programmer productivity is not uncommon. The use of idioms increases readability, while allowing API implementors to optimize through idiom recognition.

SPARSITY AND APL by Lee Courtney — last modified 2011-02-26 22:26

A definition of Sparse APL is proposed. A review of Sparse Matrix Research is presented and related to the current APL language and systems. Presented next is a discussion of the possible extensions of classic Sparse Matrix methods that would be required in a "Sparse Array" implementation of APL. This includes a discussion of a suggested research direction. Some relationships of Sparse APL to other fields outside of APL are mentioned. Finally, a list of open questions is interposed for anyone interested in pursuing some of these questions.

SHARP APL Utility Library Catalogue by Lee Courtney — last modified 2011-02-26 22:39

THIS CATALOGUE CONSISTS OF THREE PARTS: AN INDEX OF THE CATEGORIES OF THE UTILITY LIBRARY, SUMMARIES OF THE UTILITIES FOUND IN EACH CATEGORY, AND DETAILED DESCRIPTIONS OF EACH UTILITY IN THE LIBRARY.

APLIO Generalized APL-OS Interface Utilities by Lee Courtney — last modified 2011-03-19 17:02

A set of utilities for transferring data to and from the APL subsystem (in this case STSC APL/Plus) to the underlying operating system (at UTA this was IBM's OS/MVT). This was a custom written package from the Computer Center at the University of Texas at Arlington.