Difference between revisions of "Dyalog APL"

From APL Wiki
Jump to navigation Jump to search
(Influenced by NARS)
(Add history section and change introduction a little)
Line 22: Line 22:
 
}}
 
}}
 
<!-- :''For the chat bot, see [[APL Orchard#Chat bot]].'' -->
 
<!-- :''For the chat bot, see [[APL Orchard#Chat bot]].'' -->
'''Dyalog APL''', or simply '''Dyalog''', is a modern APL in the [[APL2]] tradition, first released by British company [[Dyalog Ltd.|Dyadic Systems Ltd.]] (now Dyalog Ltd.) in 1983 for the Zylog Z80 processor (the name ''Dyalog'' is a portmanteau of ''Dyadic'' and ''Zylog''). Dyalog supports several platforms and interfaces with many languages and runtimes including native [[wikipedia:Shared library|shared libraries]], [[.NET]], the [[wikipedia:Java virtual machine|JVM]], [[wikipedia:R (programming language)|R]], and [[wikipedia:Python (programming language)|Python]]. It is actively developed and has introduced many new primitives and concepts to array programming. Major categories of features introduced to APL by Dyalog are [[tacit]] programming by allowing named [[derived function]]s and later [[train]]s, lexically-scoped functional programming using [[dfn]]s, [[namespace]]s and [[object-oriented programming]], and the addition of [[leading axis theory]] and the [[Rank operator]] to the [[nested array model|nested array]] paradigm.
+
'''Dyalog APL''', or simply '''Dyalog''', is a [[Nested array model|nested]] APL based on [[NARS]] and [[APL2]], first released by British company [[Dyalog Ltd.|Dyadic Systems Ltd.]] (now Dyalog Ltd.) in 1983 for the [[wikipedia:Zilog Z8000|Zilog Z8000]] processor (the name ''Dyalog'' is a portmanteau of ''Dyadic'' and ''Zilog''). Continuously developed since, Dyalog has added support for many programming paradigms including [[object-oriented programming]] based on [[.NET]], [[wikipedia:Lisp (programming language)|Lisp]]-style lexically scoped anonymous functions ([[dfn]]s), and [[Leading axis theory|leading axis]] and [[tacit programming]] support based on [[J]]. It supports several platforms and interoperability between them, and interfaces with other languages and runtimes including native [[wikipedia:Shared library|shared libraries]], [[.NET]], the [[wikipedia:Java virtual machine|JVM]], [[wikipedia:R (programming language)|R]], and [[wikipedia:Python (programming language)|Python]].
  
In 1995, two Dyalog developers—[[John Scholes]] and [[Peter Donnelly]]—were awarded the [[Iverson Award]] for their work on the interpreter. [[Gitte Christensen]] and [[Morten Kromberg]] were joint recipients of the Iverson Award in 2016.
+
Although it initially received very little commercial interest, Dyalog has steadily grown in prominence and in the 2010s has been the basis of several new APL dialects including [[ngn/apl]], [[APL\iv]], and [[dzaima/APL]]. Even in APLs not derived from Dyalog such as [[GNU APL]] and [[NARS2000]], [[dfn]]-style function syntax has become common, and Dyalog has also popularised [[SHARP APL]] and [[J]] innovations such as the [[Rank operator]] and [[train]]s among nested APLs.
 +
 
 +
== History ==
 +
{{Main|Dyalog Ltd.}}
 +
Work on Dyalog was begun in 1981 by APL consulting company [[Dyadic Systems]], which by that time had grown to support about 15 employees. In partnership with [[wikipedia:Zilog|Zilog]] UK, Dyadic developed an interpreter using the [[wikipedia:C (programming language)|C]] programming language for the [[wikipedia:Zilog Z8000|Zilog Z8000]]'s [[wikipedia:UNIX|UNIX]] operating system—both obscure technologies at the time. Dyadic employees [[John Scholes]] and [[Geoff Streeter]] worked full-time on the implementation, while David Crossley managed its development as a part-time role. Initially aiming to produce something like [[SHARP APL]], they eventually chose a [[Nested array model|nested]] model rather than adding [[box]]es to the [[flat array model]] like SHARP, and drew most design decisions from [[STSC]]'s experimental [[NARS]] dialect and the material available at the time regarding [[IBM]]'s plans for [[APL2]].<ref name="taylor">Stephen Taylor. [http://archive.vector.org.uk/art10013790 "How we got here"]. [[Vector journal]] Volume 23 special supplement "Dyalog at 25". 2008-09.</ref>
 +
 
 +
Released at [[APL83]], Dyalog sold very few copies due to the lack of interest in either Unix or the nested array model. Subsequent sales were also limited, with only a single licence sold through Zilog partly due to the Z8000's limited popularity. Supported by Dyadic's APL consulting and later by sales of Unix hardware, Scholes and Streeter continued work on Dyalog by porting it to a wide variety of Unix systems in response to requests from users; in 1995, Scholes was awarded the [[Iverson Award]] jointly with [[Peter Donnelly]] for his work on the Dyalog interpreter. Although it continued to run significant losses every year, Dyalog slowly acquired users during the 1980s, including current client [[wikipedia:SimCorp|SimCorp]]. In 1991, Dyadic hired [[John Daintree]] to begin work on the <source lang=apl inline>⎕WC</source> graphical user interface for [[wikipedia:Microsoft Windows|Microsoft Windows]]; Dyalog for Windows debuted at [[APL92]] and quickly become Dyalog's main platform.<ref name="taylor"/>
 +
 
 +
In 1996, John Scholes introduced a new form of functional definition to Dyalog based on his studies of the functional programming language [[wikipedia:Scheme (programming language)|Scheme]], which he called [[dfn]]s, for "direct functions". Rarely used for many years, dfns have become a common APL feature, with many newer APLs removing traditional [[defined function]]s from the language in favour of dfns. Another major addition to the language began in 2000, when John Daintree was invited to participate in the design of Microsoft's [[.NET]]. Based on this work, and the [[namespace]]s which he had added to the language in 1994, Daintree developed an [[Object-oriented programming|object]] model for Dyalog, which was released in 2006. These efforts also led to the new language initially called Dyalog.NET and later [[APL#]], which was first released in 2010 but abandoned in 2012 when Microsoft deprecated [[wikipedia:Microsoft Silverlight|Silverlight]].
 +
 
 +
In the 2010s, Dyalog development began to focus on performance, which had been improved out of necessity in early releases but had not been a major focus. In 2010 Dyalog Ltd. hired [[Jay Foad]], a compiler developer who initially created a bytecode compiler for APL and later improved performance in other ways, and served as CTO from 2016 until his departure in 2019. In 2011 the company hired [[Roger Hui]], developer of [[J]], and in 2016 it also hired J programmer and language implementor [[Marshall Lochbaum]]. Both developers improved performance of Dyalog's primitives on flat arrays, and brought concepts such as the [[Rank operator]], [[train]]s, and composition operators [[Atop]] and [[Over]] from J to APL.
 +
 
 +
The Dyalog interpreter has also incorporated significant components written in APL in the 2000s and 2010s. [[Dan Baronet]], hired in 2006, introduced the SALT (Simple APL Library Toolkit) system to distribute APL code, and [[user command]]s based on it, in [[Dyalog APL 12.0|version 12.0]] in 2008. Work on APL components of Dyalog has also been done by [[Brian Becker]] and [[Adám Brudzewsky]]. Brudzewsky, hired in 2015, has also driven the adoption of new functionality such as [[Nest]] and [[array notation]] in Dyalog.
  
 
== Platforms ==
 
== Platforms ==

Revision as of 16:05, 22 May 2020

Dyalog APL, or simply Dyalog, is a nested APL based on NARS and APL2, first released by British company Dyadic Systems Ltd. (now Dyalog Ltd.) in 1983 for the Zilog Z8000 processor (the name Dyalog is a portmanteau of Dyadic and Zilog). Continuously developed since, Dyalog has added support for many programming paradigms including object-oriented programming based on .NET, Lisp-style lexically scoped anonymous functions (dfns), and leading axis and tacit programming support based on J. It supports several platforms and interoperability between them, and interfaces with other languages and runtimes including native shared libraries, .NET, the JVM, R, and Python.

Although it initially received very little commercial interest, Dyalog has steadily grown in prominence and in the 2010s has been the basis of several new APL dialects including ngn/apl, APL\iv, and dzaima/APL. Even in APLs not derived from Dyalog such as GNU APL and NARS2000, dfn-style function syntax has become common, and Dyalog has also popularised SHARP APL and J innovations such as the Rank operator and trains among nested APLs.

History

Main article: Dyalog Ltd.

Work on Dyalog was begun in 1981 by APL consulting company Dyadic Systems, which by that time had grown to support about 15 employees. In partnership with Zilog UK, Dyadic developed an interpreter using the C programming language for the Zilog Z8000's UNIX operating system—both obscure technologies at the time. Dyadic employees John Scholes and Geoff Streeter worked full-time on the implementation, while David Crossley managed its development as a part-time role. Initially aiming to produce something like SHARP APL, they eventually chose a nested model rather than adding boxes to the flat array model like SHARP, and drew most design decisions from STSC's experimental NARS dialect and the material available at the time regarding IBM's plans for APL2.[1]

Released at APL83, Dyalog sold very few copies due to the lack of interest in either Unix or the nested array model. Subsequent sales were also limited, with only a single licence sold through Zilog partly due to the Z8000's limited popularity. Supported by Dyadic's APL consulting and later by sales of Unix hardware, Scholes and Streeter continued work on Dyalog by porting it to a wide variety of Unix systems in response to requests from users; in 1995, Scholes was awarded the Iverson Award jointly with Peter Donnelly for his work on the Dyalog interpreter. Although it continued to run significant losses every year, Dyalog slowly acquired users during the 1980s, including current client SimCorp. In 1991, Dyadic hired John Daintree to begin work on the ⎕WC graphical user interface for Microsoft Windows; Dyalog for Windows debuted at APL92 and quickly become Dyalog's main platform.[1]

In 1996, John Scholes introduced a new form of functional definition to Dyalog based on his studies of the functional programming language Scheme, which he called dfns, for "direct functions". Rarely used for many years, dfns have become a common APL feature, with many newer APLs removing traditional defined functions from the language in favour of dfns. Another major addition to the language began in 2000, when John Daintree was invited to participate in the design of Microsoft's .NET. Based on this work, and the namespaces which he had added to the language in 1994, Daintree developed an object model for Dyalog, which was released in 2006. These efforts also led to the new language initially called Dyalog.NET and later APL#, which was first released in 2010 but abandoned in 2012 when Microsoft deprecated Silverlight.

In the 2010s, Dyalog development began to focus on performance, which had been improved out of necessity in early releases but had not been a major focus. In 2010 Dyalog Ltd. hired Jay Foad, a compiler developer who initially created a bytecode compiler for APL and later improved performance in other ways, and served as CTO from 2016 until his departure in 2019. In 2011 the company hired Roger Hui, developer of J, and in 2016 it also hired J programmer and language implementor Marshall Lochbaum. Both developers improved performance of Dyalog's primitives on flat arrays, and brought concepts such as the Rank operator, trains, and composition operators Atop and Over from J to APL.

The Dyalog interpreter has also incorporated significant components written in APL in the 2000s and 2010s. Dan Baronet, hired in 2006, introduced the SALT (Simple APL Library Toolkit) system to distribute APL code, and user commands based on it, in version 12.0 in 2008. Work on APL components of Dyalog has also been done by Brian Becker and Adám Brudzewsky. Brudzewsky, hired in 2015, has also driven the adoption of new functionality such as Nest and array notation in Dyalog.

Platforms

Besides for working out-of-the-box on Windows, macOS, and AIX, Dyalog APL runs on many Linuxes. However, to function, some require additional action beyond simple installation. As of 2019-05-15, the necessary actions for versions 16.0, 17.0, and 17.1 are:

Distribution Action
Debian 8.2, 9.8, 9.9 no pre-reqs
Fedora 29, 30 dnf install ncurses-compat-libs
Linux Mint 18.0, 19.0 no pre-reqs
openSUSE 15.0 zypper install libncurses5
CentOS/RedHat 6 not supported for 17.1 as glibc is at too low a level
CentOS/RedHat 7 no pre-reqs
RedHat 8 rpm -Uvh ncurses-compat-libs (note: RH8 would not install in a VM)
Ubuntu 16.04, 18.04 no pre-reqs
Ubuntu 19.04 apt-get install libtinfo5

Versions

Main article: Dyalog APL versions

Dyalog lists historical versions, along with release notes since 14.0, on its website. Its early history is recounted in more detail by Pete Donnelly in Dyalog APL: A Personal History (pdf).

Number Year Month Features
1 1983 April (Zilog S8000 only)
2 1984 (Many more platforms)
3.0 1985 (More platforms) Rectangular display of arrays
4.0 1986 October User-defined operators, Assignment for functions (including derived functions), ⎕MONITOR
5.0 1987 April Nested array editor
5.1 1988 April (first version for DOS) User-defined input/output tables, ⎕SM and ⎕SR, windowed editor/tracer, interface to GSS/CGI
5.2 1990 January Naked trace
6.0 1990 April GUI IDE
6.1 1990 October ⎕ED
6.2.1 1992 July (first version for Windows) ⎕WC, ⎕DQ, etc.
6.3.1 1993 April ⎕NA, graphical, clipboard and printer objects
7.0.1 1994 August Namespaces, additional GUI objects
7.1 1995 May ⎕CS, GUI objects as namespaces, greater APL2 compatibility
8.0 1996 May Keywords (:If/:Else, :Repeat/:Until, :Trap, and so on), ⎕PATH, additional GUI objects, OLE
8.1 1997 March dfns with lexical scope, syntax colouring, TCPSocket object, OLE client/server, automatic file tie numbers
8.2 1999 January Windowed Reduction and scalar functions with axis (from APL2), Threading with Spawn (&), ActiveX, :With, additional GUI objects
9.0 2000 September Namespace references (instead of string names) and dot syntax, context-sensitive help (F1), aditional GUI objects with animation
9.0.1 2001 January (Windows CE) Pocket APL
9.0.2 2002 January .NET support
9.5 2002 September
10.0 2003 March ⎕NULL, ⎕MAP, idiom recognition (mapped files), retained hash tables, .NET support built-in, run-time workspace as .exe, auto-completion, mapped
10.1 2004 July Multiple arguments in tradfn headers, thread tokens, 64-bit component files, value tips
11.0 2006 October Object-oriented programming (classes, objects, interfaces) modelled after C#, Index (), Power operator (), GCD (), LCM ()
12.0 2008 August Unicode support (⎕AVU, ⎕UCS), ⎕FCOPY, ⎕FPROPS
12.1 2009 November I-beam (), Table (), ⎕XML, ⎕FCHK, User commands
13.0 2011 April Left (), Right (), Variant (), ⎕OPT, ⎕R, ⎕S, ⎕PROFILE, ⎕RSI, complex number and decimal float support, short arguments for Take, Drop, and Index (, , )
13.1 2012 April ⎕DMX, ⎕FHIST
13.2 2013 January Array Editor
14.0 2014 June Trains, Tally (), Key (), Rank operator (), high-rank Index Of, multi-threading with futures and isolates
14.1 2015 June :Disposable .NET objects and resources, gesture support, many new I-beams
15.0 2016 June ⎕MKDIR, ⎕NDELETE, ⎕NEXISTS, ⎕NGET, ⎕NINFO, ⎕NPARTS, ⎕NPUT
16.0 2017 June At (@), Interval Index (), Where (), Nest (), Partition (), Stencil (), ⎕JSON, ⎕CSV
17.0 2018 July ⎕NCOPY, ⎕NMOVE, total array ordering, high-rank Unique
17.1 2019 October Duplicates in Interval Index () look-up array
18.0 Unreleased Atop (), Over (), Constant (), Unique Mask (), duplicates from Where (), empty partitions from Partitioned Enclose (), multi-line session input, date-time conversion, case folding/mapping (⎕C)

Primitives

Functions

Glyph Monadic Dyadic
+ Conjugate Plus
- Negate Minus
× Direction Times
÷ Reciprocal Divide
| Magnitude Residue
Floor Minimum
Ceiling Maximum
* Exponential Power
Natural Logarithm Logarithm
! Factorial Binomial
Pi Times Circular
~ Not Without
? Roll Deal
And
Or
Nand
Nor
< Less
Less Or Equal
= Equal
Greater Or Equal
> Greater
Unique Mask Not Equal
Shape Reshape
, Ravel Catenate
Table Catenate First
Reverse Rotate
Reverse First Rotate First
Transpose
Mix/First Take
Split Drop
Enclose Partitioned Enclose
Nest Partition
Enlist/Type Membership
First/Mix Pick
/ Replicate
Replicate First
\ Expand
Expand First
Intersection
Unique Union
Same Left
Same Right
Index Generator Index Of
Where Interval Index
Grade Down
Grade Up
Find
Depth Match
Tally Not Match
Execute
Format
Base
Represent
Matrix Inverse Matrix Divide
Materialise Squad Indexing

Operators

Syntax Monadic call Dyadic call
f/ Reduction Windowed Reduction
f Reduction First Windowed Reduction First
f\ Scan
f Scan First
f¨ Each
f Commute
A Constant
fv Power
f.g Inner Product
∘.f Outer Product
Ag Bind
fB
fg Beside
fB Rank
fg Atop
fg Over
f@v At
fB Variant
f Key
fB Stencil
A I-beam
f& Spawn
f[B] Axis

Implementation

Dyalog APL is implemented primarily in C with some parts implemented in C++ in order to use templates. C intrinsics are used to access instruction set extensions. Some architecture-specific assembly, both compiled separately and inline from C, is used for functionality like exception flags which is not easily accessible in C. Prior to version 17.0, assembly was also used for vectorized arithmetic. In 17.0, this code was replaced by a new C++ implementation.

Internal types

Dyalog uses the following numeric types:

  • 1-bit packed Boolean
  • 1-byte integer
  • 2-byte integer
  • 4-byte integer
  • 8-byte double
  • 16-byte complex (one double for each component)
  • 16-byte decimal float "decf" (BID or DPD)

Character encodings differ for classic and unicode interpreters: classic interpreters use a custom 1-byte encoding for all characters, and are limited to a 256-character set, while characters in unicode interpreters are 1-, 2-, or 4-byte unsigned unicode code point values.

Nested and mixed arrays (that is, pointer arrays) are always stored as arrays of pointers, while simple numeric or character arrays are always stored using one of the above types. For both numbers and characters, an array may be represented using any type that can contain all the values. The interpreter may reduce the type of an array to the minimum possible ("squeeze" the array) during execution.

Because there is no complex representation using decimal floats for the components, arrays containing both decimal floats and complex numbers have no common representation. Dyalog converts such arrays to complex numbers, resulting in a loss of precision for decf elements.

Instruction set usage

Dyalog makes heavy use of vector instructions on all platforms, as well as other special instruction sets primarily on x86. Instruction set availability is checked at runtime, so that the minimum required instruction set remains low:

  • For 32-bit x86, only SSE2 is required.
  • For x86_64, there is no minimum requirement as every processor supports SSE2. SSE4.1 is required on macOS as all x86 Apple machines support this instruction set.
  • For ARM32, there is no minimum requirement.
  • As of version 17.1, POWER7 and above are supported. Support for older systems is dropped because Dyalog compiles separate binaries for each POWER architecture.

In Dyalog 17.0, the code for vectorized scalar functions was unified and extended to allow Intel AVX2 and ARM NEON in addition to Intel SSE2 and SSE4.1, and AltiVec VMX for IBM POWER. This code is also used for operations involving the scalar dyadics Plus, Minus, Times, Divide, Maximum, Minimum, and comparison functions, as well as some functions derived from operators applied to these functions, such as the Outer Product and Inner Product.

Dyalog also uses many other x86 extensions:

It also uses the POWER8 gather-bits-by-bytes instruction, which is equivalent to transposing an 8x8 bit matrix for Boolean Transpose since version 15.0 (expanded in applicability in 16.0) and the fused multiply-add instruction for division like x86 FMA3 in 18.0.

External links


APL dialects [edit]
Maintained APL+Win (APL*PLUS) ∙ APL2APL64APL\ivAprilCo-dfnsDyalog APLdzaima/APLGNU APLNARS2000ngn/apl
Historical Iverson notationA Programming LanguageA+ (A) ∙ APL#APL.68000APL.SVAPLXAPL\1130APL\360NARSopenAPLRowanSAXSHARP APLVisualAPL (APLNext) ∙ VS APLYork APL
Derivatives AHPLAPL\ivELIIIvyJJellyK (Q, KDB+) ∙ LYaPASNialRAD
  1. 1.0 1.1 Stephen Taylor. "How we got here". Vector journal Volume 23 special supplement "Dyalog at 25". 2008-09.