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![]() GNU Octave 4.3.0+ running on Linux | |
Developer(s) | John W. Eaton and many others [1] |
---|---|
Initial release | 4 January 1993 17 February, 1994 (version 1.0) [2] | (first alpha release)
Stable release | |
Repository | |
Written in | C++ (main), Octave itself (scripts), C (wrapper code), Fortran (linear algebra wrapper code) [4] |
Operating system | Windows, macOS, Linux, BSD |
Available in | 18 languages [5] |
Type | Scientific computing |
License | 2007: GPL-3.0-or-later [lower-alpha 1] 1992: GPL-2.0-or-later [lower-alpha 2] |
Website | octave |
GNU Octave is a scientific programming language for scientific computing and numerical computation. Octave helps in solving linear and nonlinear problems numerically, and for performing other numerical experiments using a language that is mostly compatible with MATLAB. It may also be used as a batch-oriented language. As part of the GNU Project, it is free software under the terms of the GNU General Public License.
The project was conceived around 1988. [6] At first it was intended to be a companion to a chemical reactor design course. Full development was started by John W. Eaton in 1992. The first alpha release dates back to 4 January 1993 and on 17 February 1994 version 1.0 was released. Version 8.4.0 was released on 5 November 2023. [7]
The program is named after Octave Levenspiel, a former professor of the principal author. Levenspiel was known for his ability to perform quick back-of-the-envelope calculations. [8]
Time | Action |
---|---|
1988/1989 | 1st discussions (Book and Software) |
February 1992 | Start of Development |
January 1993 | News in Web (Version 0.60) |
February 1994 | 1st Publication (Version 1.0.0 to 1.1.1) [9] |
December 1996 | 2nd Publication (Version 2.0.x) with Windows Port (Cygwin) [10] |
December 2007 | Publication of Version 3.0 (Milestone) [11] |
29 May 2015 | Version 4.0.0 (stable GUI and new Syntax for OOP) [12] [13] [14] [15] |
1 March 2019 | Publication of Octave 5.1.0 (QT5 preferred, Qt 4.8 minimum), hiDpi support [16] |
26 November 2020 | Publication of Octave 6.1.0 (QT5 preferred, Qt 4.x deprecated for remove in 7) [17] |
6 April 2022 | Publication of Octave 7.1.0 (QT5 preferred), improved graphics backend and matlab compatibility [18] |
7 March 2023 | Publication of Octave 8.1.0, improved graphics backend and matlab compatibility [19] |
14 March 2024 | Publication of Octave 9.1.0, general, matlab compatibility, and graphics improvements. [20] |
In addition to use on desktops for personal scientific computing, Octave is used in academia and industry. For example, Octave was used on a massive parallel computer at Pittsburgh Supercomputing Center to find vulnerabilities related to guessing social security numbers. [21]
Acceleration with OpenCL or CUDA is also possible with use of GPUs. [22]
The Octave language is an interpreted programming language. It is a structured programming language (similar to C) and supports many common C standard library functions, and also certain UNIX system calls and functions. [23] However, it does not support passing arguments by reference [24] although function arguments are copy-on-write to avoid unnecessary duplication.
Octave programs consist of a list of function calls or a script. The syntax is matrix-based and provides various functions for matrix operations. It supports various data structures and allows object-oriented programming. [25]
Its syntax is very similar to MATLAB, and careful programming of a script will allow it to run on both Octave and MATLAB. [26]
Because Octave is made available under the GNU General Public License, it may be freely changed, copied and used. [8] The program runs on Microsoft Windows and most Unix and Unix-like operating systems, including Linux, Android, and macOS. [27] [28] [29]
Typing a TAB character on the command line causes Octave to attempt to complete variable, function, and file names (similar to Bash's tab completion). Octave uses the text before the cursor as the initial portion of the name to complete. [30]
When running interactively, Octave saves the commands typed in an internal buffer so that they can be recalled and edited.
Octave includes a limited amount of support for organizing data in structures. In this example, we see a structure x with elements a, b, and c, (an integer, an array, and a string, respectively):
octave:1>x.a=1;x.b=[1,2;3,4];x.c="string";octave:2>x.aans=1octave:3>x.bans=1234octave:4>x.cans=stringoctave:5>xx=scalarstructurecontainingthefields:a=1b=1234c=string
Octave's &&
and ||
logical operators are evaluated in a short-circuit fashion (like the corresponding operators in the C language), in contrast to the element-by-element operators &
and |
.
Octave includes the C-like increment and decrement operators ++
and --
in both their prefix and postfix forms. Octave also does augmented assignment, e.g. x += 5
.
Octave supports a limited form of exception handling modelled after the unwind_protect
of Lisp. The general form of an unwind_protect block looks like this:
unwind_protectbodyunwind_protect_cleanupcleanupend_unwind_protect
As a general rule, GNU Octave recognizes as termination of a given block
either the keyword end
(which is compatible with the MATLAB language) or a more specific keyword endblock
or, in some cases, end_block
. As a consequence, an unwind_protect
block can be terminated either with the keyword end_unwind_protect
as in the example, or with the more portable keyword end
.
The cleanup part of the block is always executed. In case an exception is raised by the body part, cleanup is executed immediately before propagating the exception outside the block unwind_protect
.
GNU Octave also supports another form of exception handling (compatible with the MATLAB language):
trybodycatchexception_handlingend
This latter form differs from an unwind_protect
block in two ways. First, exception_handling is only executed when an exception is raised by body. Second, after the execution of exception_handling the exception is not propagated outside the block (unless a rethrow( lasterror )
statement is explicitly inserted within the exception_handling code).
Octave has a mechanism for handling functions that take an unspecified number of arguments without explicit upper limit. To specify a list of zero or more arguments, use the special argument varargin
as the last (or only) argument in the list. varargin
is a cell array containing all the input arguments.
functions=plus (varargin)if(nargin==0)s=0;elses=varargin{1}+plus(varargin{2:nargin});endend
A function can be set up to return any number of values by using the special return value varargout
. For example:
functionvarargout=multiassign (data)fork=1:nargoutvarargout{k}=data(:,k);endend
It is also possible to execute Octave code directly in a C++ program. For example, here is a code snippet for calling rand([10,1])
:
#include<octave/oct.h>...ColumnVectorNumRands(2);NumRands(0)=10;NumRands(1)=1;octave_value_listf_arg,f_ret;f_arg(0)=octave_value(NumRands);f_ret=feval("rand",f_arg,1);Matrixunis(f_ret(0).matrix_value());
C and C++ code can be integrated into GNU Octave by creating oct files, or using the MATLAB compatible MEX files.
Octave has been built with MATLAB compatibility in mind, and shares many features with MATLAB:
Octave treats incompatibility with MATLAB as a bug; therefore, it could be considered a software clone, which does not infringe software copyright as per Lotus v. Borland court case.
MATLAB scripts from the MathWorks' FileExchange repository in principle are compatible with Octave. However, while they are often provided and uploaded by users under an Octave compatible and proper open source BSD license, the FileExchange Terms of use prohibit any usage beside MathWorks' proprietary MATLAB. [31] [32] [33]
There are a few purposeful, albeit minor, syntax additions Archived 2012-04-26 at the Wayback Machine :
Many, but not all, of the numerous MATLAB functions are available in GNU Octave, some of them accessible through packages in Octave Forge. The functions available as part of either core Octave or Forge packages are listed online Archived 2024-03-14 at the Wayback Machine .
A list of unavailable functions is included in the Octave function __unimplemented.m__
. Unimplemented functions are also listed under many Octave Forge packages in the Octave Wiki.
When an unimplemented function is called the following error message is shown:
octave:1>guidewarning:the'guide'functionisnotyetimplementedinOctavePleaseread<http://www.octave.org/missing.html>tolearnhowyoucancontributemissingfunctionality.error:'guide'undefinednearline1column1
Octave comes with an official graphical user interface (GUI) and an integrated development environment (IDE) based on Qt. It has been available since Octave 3.8, [34] and has become the default interface (over the command-line interface) with the release of Octave 4.0. [12] It was well-received by an EDN contributor, who wrote "[Octave] now has a very workable GUI" in reviewing the then-new GUI in 2014. [35]
Several 3rd-party graphical front-ends have also been developed, like ToolboX for coding education.
With Octave code, the user can create GUI applications. See GUI Development (GNU Octave (version 7.1.0)). Below are some examples:
Button, edit control, checkbox
# create figure and panel on itf=figure;# create a button (default style)b1=uicontrol(f,"string","A Button","position",[101015040]);# create an edit controle1=uicontrol(f,"style","edit","string","editable text","position",[106030040]);# create a checkboxc1=uicontrol(f,"style","checkbox","string","a checkbox","position",[1012015040]);
Textbox
prompt={"Width","Height","Depth"};defaults={"1.10","2.20","3.30"};rowscols=[1,10;2,20;3,30];dims=inputdlg(prompt,"Enter Box Dimensions",rowscols,defaults);
Listbox with message boxes.
my_options={"An item","another","yet another"};[sel,ok]=listdlg("ListString",my_options,"SelectionMode","Multiple");if(ok==1)msgbox("You selected:");fori=1:numel(sel)msgbox(sprintf("\t%s",my_options{sel(i)}));endforelsemsgbox("You cancelled.");endif
Radiobuttons
# create figure and panel on itf=figure;# create a button groupgp=uibuttongroup(f,"Position",[00.511])# create a buttons in the groupb1=uicontrol(gp,"style","radiobutton","string","Choice 1","Position",[1015010050]);b2=uicontrol(gp,"style","radiobutton","string","Choice 2","Position",[105010030]);# create a button not in the groupb3=uicontrol(f,"style","radiobutton","string","Not in the group","Position",[105010050]);
Octave also has many packages available. Those packages are located at Octave-Forge Octave Forge - Packages, or Github Octave Packages. It is also possible for anyone to create and maintain packages.
Other free alternatives to MATLAB include Scilab and FreeMat. [36] [37] [38] [39] Octave is more compatible with MATLAB than Scilab is, [36] [40] [41] and FreeMat has not been updated since June 2013. [42]
Bash, short for Bourne-Again SHell, is a shell program and command language supported by the Free Software Foundation and first developed for the GNU Project by Brian Fox. Designed as a 100% free software alternative for the Bourne shell, it was initially released in 1989. Its moniker is a play on words, referencing both its predecessor, the Bourne shell, and the concept of rebirth.
The GNU Debugger (GDB) is a portable debugger that runs on many Unix-like systems and works for many programming languages, including Ada, Assembly, C, C++, D, Fortran, Haskell, Go, Objective-C, OpenCL C, Modula-2, Pascal, Rust, and partially others.
MATLAB is a proprietary multi-paradigm programming language and numeric computing environment developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages.
Pascal is an imperative and procedural programming language, designed by Niklaus Wirth as a small, efficient language intended to encourage good programming practices using structured programming and data structuring. It is named after French mathematician, philosopher and physicist Blaise Pascal.
gnuplot is a command-line and GUI program that can generate two- and three-dimensional plots of functions, data, and data fits. The program runs on all major computers and operating systems . Originally released in 1986, its listed authors are Thomas Williams, Colin Kelley, Russell Lang, Dave Kotz, John Campbell, Gershon Elber, Alexander Woo "and many others." Despite its name, this software is not part of the GNU Project.
GNU Bison, commonly known as Bison, is a parser generator that is part of the GNU Project. Bison reads a specification in Bison syntax, warns about any parsing ambiguities, and generates a parser that reads sequences of tokens and decides whether the sequence conforms to the syntax specified by the grammar.
In computing, dir
(directory) is a command in various computer operating systems used for computer file and directory listing. It is one of the basic commands to help navigate the file system. The command is usually implemented as an internal command in the command-line interpreter (shell). On some systems, a more graphical representation of the directory structure can be displayed using the tree
command.
In computing, a stack trace is a report of the active stack frames at a certain point in time during the execution of a program. When a program is run, memory is often dynamically allocated in two places: the stack and the heap. Memory is continuously allocated on a stack but not on a heap, thus reflective of their names. Stack also refers to a programming construct, thus to differentiate it, this stack is referred to as the program's function call stack. Technically, once a block of memory has been allocated on the stack, it cannot be easily removed as there can be other blocks of memory that were allocated before it. Each time a function is called in a program, a block of memory called an activation record is allocated on top of the call stack. Generally, the activation record stores the function's arguments and local variables. What exactly it contains and how it's laid out is determined by the calling convention.
gretl is an open-source statistical package, mainly for econometrics. The name is an acronym for GnuRegression, Econometrics and Time-seriesLibrary.
The following tables provide a comparison of numerical analysis software.
MPSolve is a package for the approximation of the roots of a univariate polynomial. It uses the Aberth method, combined with a careful use of multiprecision.
In computing, help
is a command in various command line shells such as COMMAND.COM
, cmd.exe
, Bash, qshell, 4DOS/4NT, Windows PowerShell, Singularity shell, Python, MATLAB and GNU Octave. It provides online information about available commands and the shell environment.
Genius is a free open-source numerical computing environment and programming language, similar in some aspects to MATLAB, GNU Octave, Mathematica and Maple. Genius is aimed at mathematical experimentation rather than computationally intensive tasks. It is also very useful as just a calculator. The programming language is called GEL and aims to have a mathematically friendly syntax. The software comes with a command-line interface and a GUI, which uses the GTK+ libraries. The graphical version supports both 2D and 3D plotting. The graphical version includes a set of tutorials originally aimed at in class demonstrations.
20-sim is a commercial modeling and simulation program for multi-domain dynamic systems, which is developed by Controllab. With 20-sim, models can be entered as equations, block diagrams, bond graphs and physical components. 20-sim is used for modeling complex multi-domain systems and for the development of control systems.
JData is a light-weight data annotation and exchange open-standard designed to represent general-purpose and scientific data structures using human-readable (text-based) JSON and (binary) UBJSON formats. JData specification specifically aims at simplifying exchange of hierarchical and complex data between programming languages, such as MATLAB, Python, JavaScript etc. It defines a comprehensive list of JSON-compatible "name":value
constructs to store a wide range of data structures, including scalars, N-dimensional arrays, sparse/complex-valued arrays, maps, tables, hashes, linked lists, trees and graphs, and support optional data grouping and metadata for each data element. The generated data files are compatible with JSON/UBJSON specifications and can be readily processed by most existing parsers. JData-defined annotation keywords also permit storage of strongly-typed binary data streams in JSON, data compression, linking and referencing.