View source for GNU Octave

{{Short description|Numerical analysis programming language}}
{{Other uses|Octave (disambiguation)}}
{{Infobox software
| name = GNU Octave
| logo = [[File:Gnu-octave-logo.svg|100px]]
| screenshot = GNUOctave430.png
| caption = GNU Octave 4.3.0+ running on [[Linux]]
| developer = John W. Eaton and many others<ref>{{cite web|title=contributors.in|author=Rik|url=http://hg.savannah.gnu.org/hgweb/octave/file/tip/doc/interpreter/contributors.in|access-date=14 June 2015|date=10 June 2015}}</ref>
| released = {{Start date and age|4 January 1993}} (first alpha release)<br/>{{Start date and age|17 February 1994}} (version 1.0)<ref name="kilikilikili">{{cite web| url = https://www.gnu.org/software/octave/about| title = "Full-time development began in the Spring of 1992. The first alpha release was January 4, 1993, and version 1.0 was released February 17, 1994."}}</ref>
| latest release version = {{wikidata|property|preferred|references|edit|Q223679|P348|P548=Q2804309}}
| latest release date = {{start date and age|{{wikidata|qualifier|P548=Q2804309|P348|P577}}}}
| latest preview version = {{wikidata|property|preferred|references|edit|Q223679|P348|P548=Q51930650}}
| latest preview date = {{wikidata|qualifier|preferred|single|Q223679|P348|P548=Q51930650|P577}}
| programming language = [[C++]] (main), Octave itself (scripts), [[C (programming language)|C]] (wrapper code), [[Fortran]] (linear algebra wrapper code)<ref name="octave_building">{{cite web|title=Building - Octave|url=https://wiki.octave.org/Building|website=wiki.octave.org|publisher=GNU|access-date=1 May 2018|language=en}}</ref>
| operating system = [[Windows]], [[macOS]], [[Linux]], [[Berkeley Software Distribution|BSD]]
| platform = <!--List them all-->
| language count = 18
| language footnote = <ref>{{Cite web|url=https://hg.savannah.gnu.org/hgweb/octave/file/4730becad0b1/libgui/languages|title=Basque, Belarusian, Catalan, Chinese, Dutch, English, French, German, Hungarian, Italian, Japanese, Latvian, Portuguese (Brazil), Portuguese (Portugal), Russian, Spanish, Turkish, Ukrainian|website=hg.savannah.gnu.org}}</ref>
| genre = [[List of numerical-analysis software|Scientific computing]]
| license = 2007: [[GNU General Public License|GPL-3.0-or-later]]{{efn|GPL-3.0-or-later since 2007-10-12.}}<br />1992: [[GNU General Public License|GPL-2.0-or-later]]{{efn|GPL-2.0-or-later from 1992-02-19 until 2007-10-11.}}
| website = https://octave.org/
}}
'''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 processing|batch-oriented]] language. As part of the [[GNU Project]], it is [[free software]] under the terms of the [[GNU General Public License]].

==History==
The project was conceived around 1988.<ref name="Octave_about">{{cite web|title=About GNU Octave|url=https://www.gnu.org/software/octave/about.html|website=www.gnu.org|publisher=GNU|access-date=1 May 2018}}</ref> 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 9.2.0 was released on 7 June 2024.<ref name=":0">{{Cite web |date=2024-06-07 |title=Octave 9.2.0 Released |url=https://octave.org/news/release/2024/06/07/octave-9.2.0-released.html |access-date=2024-11-05 |website=octave.org |language=en}}</ref>

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 calculation]]s.<ref name="about">{{cite web
| last = Eaton
| first = John W
| title = About Octave
| url = https://www.gnu.org/software/octave/about.html
| access-date = 2009-06-28 }}</ref>

== Development history ==
{| class="wikitable"
|-
! Time !! Action
|-
|style="text-align: right; white-space: nowrap;"| 1988/1989 || 1st discussions (Book and Software)
|-
|style="text-align: right; white-space: nowrap;"| February 1992 || Start of Development 
|-
|style="text-align: right; white-space: nowrap;"| January 1993 || News in Web (Version 0.60)
|-
|style="text-align: right; white-space: nowrap;"| February 1994 || 1st Publication (Version 1.0.0 to 1.1.1)<ref>{{Cite web|url=https://www.gnu.org/software/octave/NEWS-1.html|title=GNU Octave Version 1|website=www.gnu.org}}</ref>
|-
|style="text-align: right; white-space: nowrap;"| December 1996 || 2nd Publication (Version 2.0.x) with Windows Port ([[Cygwin]])<ref>{{Cite web|url=https://www.gnu.org/software/octave/NEWS-2.html|title=GNU Octave Version 2|website=www.gnu.org}}</ref>
|-
|style="text-align: right; white-space: nowrap;"| December 2007 || Publication of Version 3.0 (Milestone)<ref>{{Cite web|url=https://www.gnu.org/software/octave/NEWS-3.html|title=GNU Octave Version 3|website=www.gnu.org}}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 29 May 2015 || Version 4.0.0 (stable GUI and new Syntax for [[object oriented programming|OOP]])<ref name="auto">{{Cite web|url=https://www.gnu.org/software/octave/NEWS-4.0.html|title=GNU Octave Version 4.0|website=www.gnu.org}}</ref><ref>{{Cite web|url=https://www.gnu.org/software/octave/news/release/2015/05/29/octave-4.0.0-released.html|title=GNU Octave 4.0.0 Released|website=www.gnu.org|date=29 May 2015 }}</ref><ref>{{Cite web|url=https://www.gnu.org/software/octave/news/release/2016/03/23/octave-4.0.1-released.html|title=GNU Octave 4.0.1 Released|website=www.gnu.org|date=23 March 2016 }}</ref><ref>{{Cite web|url=https://www.gnu.org/software/octave/news/release/2016/07/02/octave-4.0.3-released.html|title=GNU Octave 4.0.3 Released|website=www.gnu.org|date=2 July 2016 }}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 1 March 2019 || Publication of Octave 5.1.0 (QT5 preferred, Qt 4.8 minimum), hiDpi support<ref>{{Cite web|url=https://www.gnu.org/software/octave/NEWS-5.1.html|title=GNU Octave Version 5|website=www.gnu.org}}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 26 November 2020 || Publication of Octave 6.1.0 (QT5 preferred, Qt 4.x deprecated for remove in 7)<ref>{{Cite web|url=https://www.gnu.org/software/octave/news/release/2020/11/26/octave-6.1.0-released.html|title=GNU Octave 6.1.0 Released|website=www.gnu.org|date=26 November 2020 }}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 6 April 2022 || Publication of Octave 7.1.0 (QT5 preferred), improved graphics backend and matlab compatibility<ref>{{Cite web|url=https://www.gnu.org/software/octave/news/release/2022/04/06/octave-7.1.0-released.html|title=GNU Octave 7.1.0 Released|website=www.gnu.org|date=6 April 2022 }}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 7 March 2023 || Publication of Octave 8.1.0, improved graphics backend and matlab compatibility<ref>{{Cite web|url=https://octave.org/news/release/2023/03/07/octave-8.1.0-released.html|title=GNU Octave 8.1.0 Released|website=octave.org|date=7 March 2023 }}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 14 March 2024 || Publication of Octave 9.1.0, general, matlab compatibility, and graphics improvements.<ref>{{Cite web |title=GNU Octave Version 9 |url=https://octave.org/NEWS-9.html |access-date=2024-03-25 |website=octave.org |language=en}}</ref>
|-
|style="text-align: right; white-space: nowrap;"| 7 June 2024 || Publication of Octave 9.2.0, bug and GUI fixes.<ref>{{Cite web |title=Octave 9.2.0 released |url=https://octave.org/news/release/2024/06/07/octave-9.2.0-released.html |access-date=2024-11-05 |website=octave.org |date=7 June 2024 |language=en}}</ref>
|}

==Developments==
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 computing|parallel]] computer at [[Pittsburgh Supercomputing Center]] to find vulnerabilities related to guessing social security numbers.<ref>{{cite web
|url=http://www.hpcwire.com/industry/government/Social-Security-Number-Vulnerability-Findings-Relied-on-Supercomputing-50292227.html
|title=Social Security Number Vulnerability Findings Relied on Supercomputing
|date=8 July 2009
|archive-url=https://web.archive.org/web/20120229220547/http://www.hpcwire.com/hpcwire/2009-07-08/social_security_number_vulnerability_findings_relied_on_supercomputing.html
|archive-date=29 February 2012
}}</ref>

Acceleration with [[OpenCL]] or [[CUDA]] is also possible with use of GPUs.<ref>{{Cite web|url=https://developer.nvidia.com/blog/drop-in-acceleration-gnu-octave/|title=Drop-in Acceleration of GNU Octave|date=June 5, 2014|website=NVIDIA Developer Blog}}</ref>

==Technical details==
* Octave is written in [[C++]] using the [[C++ standard library]].
* Octave uses an [[Interpreter (computing)|interpreter]] to execute the Octave scripting language.
* Octave is extensible using dynamically loadable modules.
* Octave interpreter has an [[OpenGL]]-based graphics engine to create plots, graphs and charts and to save or print them. Alternatively, [[gnuplot]] can be used for the same purpose.
* Octave includes a [[graphical user interface]] (GUI) in addition to the traditional [[command-line interface]] (CLI); see [[#User interfaces]] for details.

==Octave, the language==
The Octave language is an interpreted programming language. It is a [[structured programming]] language (similar to [[C (programming language)|C]]) and supports many common [[C standard library]] functions, and also certain [[POSIX|UNIX]] system calls and functions.<ref>{{cite web
| url        = http://www.network-theory.co.uk/docs/octave3/octave_269.html
| title        = GNU Octave - Controlling subprocesses
| access-date        = 2009-01-28
| date        = 14 November 2008
| archive-url        = https://web.archive.org/web/20090107005339/http://www.network-theory.co.uk/docs/octave3/octave_269.html
| archive-date        = 7 January 2009
| url-status        = dead
}}</ref> However, it does not support passing arguments by reference<ref>{{cite web
| url        = http://www.delorie.com/gnu/docs/octave/octave_105.html
| title      = GNU Octave
| access-date = 2009-01-28
}}</ref> although function arguments are [[copy-on-write]] to avoid unnecessary duplication.

Octave programs consist of a list of function calls or a [[Script (computer programming)|script]]. The syntax is [[Array programming|matrix]]-based and provides various functions for matrix operations. It supports various [[data structure]]s and allows [[object-oriented programming]].<!--Candidate for expansion--><ref>{{cite web
| url        = https://www.gnu.org/software/octave/NEWS-3.2.html
| title      = Summary of important user-visible changes for version 3.2
| access-date = 2012-01-05
}}</ref>

Its syntax is very similar to MATLAB, and careful programming of a script will allow it to run on both Octave and MATLAB.<ref>{{cite web
| url        = http://www.octave.org/wiki/index.php?title=FAQ#Porting_programs_from_Matlab_to_Octave
| title        = FAQ: MATLAB compatibility
| access-date        = 2009-04-04
| archive-date        = 2011-11-21
| archive-url        = https://web.archive.org/web/20111121043348/http://octave.org/wiki/index.php?title=FAQ#Porting_programs_from_Matlab_to_Octave
| url-status        = dead
}}</ref>

Because Octave is made available under the [[GNU General Public License]], it may be freely changed, copied and used.<ref name="about" /> The program runs on [[Microsoft Windows]] and most [[Unix]] and [[Unix-like]] [[operating system]]s, including [[Linux]], [[Android (operating system)|Android]], and [[macOS]].<ref>{{cite web
| url        = http://www.octave.org/wiki/index.php?title=FAQ#On_what_platforms_does_Octave_run.3F
| title        = FAQ: Getting Octave
| access-date        = 2009-04-04
| archive-date        = 2011-11-21
| archive-url        = https://web.archive.org/web/20111121043348/http://octave.org/wiki/index.php?title=FAQ#On_what_platforms_does_Octave_run.3F
| url-status        = dead
}}</ref><ref>{{Cite web|url=https://octave.org/doc/v6.3.0/|title=Top (GNU Octave (version 6.3.0))|website=octave.org}}</ref><ref>{{Cite web|title=Octave for Android - Octave|url=https://wiki.octave.org/Octave_for_Android|access-date=2021-08-23|website=wiki.octave.org}}</ref>

==Notable features==

===Command and variable name completion===
Typing a TAB character on the command line causes Octave to attempt to complete variable, function, and file names (similar to [[Bash (Unix shell)|Bash]]'s [[tab completion]]). Octave uses the text before the cursor as the initial portion of the name to complete.<ref>{{cite web|url=https://www.gnu.org/software/octave/doc/interpreter/Commands-For-Completion.html#Commands-For-Completion|title=Letting Readline Type For You|work=GNU Octave Reference Manual|last=Eaton|first=John W.|access-date=2016-07-29|archive-date=2018-02-12|archive-url=https://web.archive.org/web/20180212145842/http://www.gnu.org/software/octave/doc/interpreter/Commands-for-Completion.html#Commands-For-Completion|url-status=dead}}</ref>

===Command history===
When running interactively, Octave saves the commands typed in an internal buffer so that they can be recalled and edited.

===Data structures===
Octave includes a limited amount of support for organizing data in structures. In this example, we see a structure {{mono|x}} with elements {{mono|a}},  {{mono|b}}, and {{mono|c}}, (an integer, an array, and a string, respectively):
<syntaxhighlight lang="octave">
octave:1> x.a = 1; x.b = [1, 2; 3, 4]; x.c = "string";
octave:2> x.a
ans =  1
octave:3> x.b
ans =

   1   2
   3   4

octave:4> x.c
ans = string
octave:5> x
x =

  scalar structure containing the fields:

    a = 1
    b =

       1   2
       3   4

    c = string
</syntaxhighlight>

===Short-circuit Boolean operators===
Octave's <code>&&</code> and <code>||</code> logical [[Operator (programming)|operators]] are evaluated in a [[Short-circuit evaluation|short-circuit]] fashion (like the corresponding operators in the [[C (programming language)|C]] language), in contrast to the element-by-element operators <code>&</code> and <code>|</code>.

===Increment and decrement operators===
{{Main|Increment and decrement operators}}
Octave includes the C-like [[increment and decrement operators]] <code>++</code> and <code>--</code> in both their prefix and postfix forms.
Octave also does [[augmented assignment]], e.g.  <code>x += 5</code>.

===Unwind-protect===
Octave supports a limited form of [[exception handling]] modelled after the [http://www.lispworks.com/documentation/HyperSpec/Body/s_unwind.htm <code>unwind_protect</code>] of [[Lisp (programming language)|Lisp]]. The general form of an unwind_protect block looks like this:
<syntaxhighlight lang="octave">
unwind_protect
   body
unwind_protect_cleanup
   cleanup
end_unwind_protect
</syntaxhighlight>

As a general rule, GNU Octave recognizes as termination of a given <code>''block''</code> either the keyword <code>end</code> (which is compatible with the MATLAB language) or a more specific keyword <code>end''block''</code> or, in some cases, <code>end_''block''</code>. As a consequence, an <code>unwind_protect</code> block can be terminated either with the keyword <code>end_unwind_protect</code> as in the example, or with the more portable keyword <code>end</code>.

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 <code>unwind_protect</code>.

GNU Octave also supports another form of exception handling (compatible with the MATLAB language):
<syntaxhighlight lang="matlab">
try
   body
catch
   exception_handling
end
</syntaxhighlight>

This latter form differs from an <code>unwind_protect</code> 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 <code>rethrow( lasterror )</code> statement is explicitly inserted within the ''exception_handling'' code).

===Variable-length argument lists===
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 <code>varargin</code> as the last (or only) argument in the list. <code>varargin</code> is a cell array containing all the input arguments.

<syntaxhighlight lang="octave">
function s = plus (varargin)
   if (nargin==0)
      s = 0;
   else
      s = varargin{1} + plus (varargin{2:nargin});
   end
end
</syntaxhighlight>

===Variable-length return lists===
A function can be set up to return any number of values by using the special return value <code>varargout</code>. For example:

<syntaxhighlight lang="octave">
function varargout = multiassign (data)
   for k=1:nargout
      varargout{k} = data(:,k);
   end
end
</syntaxhighlight>

===C++ integration===
It is also possible to execute Octave code directly in a C++ program. For example, here is a code snippet for calling <code>rand([10,1])</code>:
<syntaxhighlight lang="cpp">
#include <octave/oct.h>
...
ColumnVector NumRands(2);
NumRands(0) = 10;
NumRands(1) = 1;
octave_value_list f_arg, f_ret;
f_arg(0) = octave_value(NumRands);
f_ret = feval("rand", f_arg, 1);
Matrix unis(f_ret(0).matrix_value());
</syntaxhighlight>

C and C++ code can be integrated into GNU Octave by creating oct files, or using the MATLAB compatible [[MEX file]]s.

=={{anchor|MATLAB}} MATLAB compatibility==
Octave has been built with MATLAB compatibility in mind, and shares many features with MATLAB:

# Matrices as fundamental data type.
# Built-in support for complex numbers.
# Powerful built-in math functions and extensive function libraries.
# Extensibility in the form of user-defined functions.

Octave treats incompatibility with MATLAB as a [[Bug (software)|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 [[License compatibility|compatible]] and proper [[open-source license|open source]] [[BSD license]], the FileExchange [[EULA|Terms of use]] prohibit any usage beside MathWorks' [[proprietary software|proprietary]] MATLAB.<ref>{{Cite web |title=FAQ - Octave |url=https://wiki.octave.org/FAQ |access-date=2022-12-05 |website=wiki.octave.org}}</ref><ref>{{Cite web |title=MATLAB Central Terms of Use |url=https://www.mathworks.com/matlabcentral/content/terms-of-use.html |access-date=2022-12-05 |website=www.mathworks.com |language=en}}</ref><ref>{{Cite web |title=File Exchange Licensing FAQ |url=https://www.mathworks.com/matlabcentral/content/fx/fx-transition-faq.html |access-date=2022-12-05 |website=www.mathworks.com |language=en}}</ref>

===Syntax compatibility===
There are a few purposeful, albeit minor, [http://octave.org/wiki/index.php?title=FAQ#Porting_programs_from_Matlab_to_Octave syntax additions] {{Webarchive|url=https://web.archive.org/web/20120426060857/http://octave.org/wiki/index.php?title=FAQ#Porting_programs_from_Matlab_to_Octave |date=2012-04-26 }}:

# [[Comment (computer programming)|Comment]] lines can be prefixed with the # character as well as the % character;
# Various [[C (programming language)|C-based]] operators [[Increment operator|++]], [[Decrement operator|--]], [[Augmented assignment|+=]], *=, /= are supported;
# Elements can be referenced without creating a new variable by cascaded indexing, e.g. [1:10](3);
# [[String (computer science)|String]]s can be defined with the double-quote " character as well as the single-quote ' character;
# When the variable type is [[Single-precision floating-point format|single]] (a single-precision floating-point number), Octave calculates the "[[mean]]" in the single-domain (MATLAB in [[Double-precision floating-point format|double-domain]]) which is faster but gives less accurate results;
# Blocks can also be terminated with more specific [[Control structure]] keywords, i.e., endif, endfor, endwhile, etc.;
# Functions can be defined within scripts and at the Octave prompt;
# Presence of a do-until loop (similar to [[Do while loop|do-while]] in C).

===Function compatibility===
Many, but not all, of the numerous MATLAB functions are available in GNU Octave, some of them accessible through packages in [https://octave.sourceforge.io Octave Forge]. The functions available as part of either core Octave or Forge packages are listed [https://octave.sourceforge.io/list_functions.php?q=&sort=alphabetic online] {{Webarchive|url=https://web.archive.org/web/20240314051049/https://octave.sourceforge.io/list_functions.php?q=&sort=alphabetic |date=2024-03-14 }}.

A list of unavailable functions is included in the Octave function  [http://hg.savannah.gnu.org/hgweb/octave/file/tip/scripts/help/__unimplemented__.m <code>__unimplemented.m__</code>]. Unimplemented functions are also listed under many Octave Forge packages in the [https://wiki.octave.org/Category:Octave_Forge Octave Wiki].

When an unimplemented function is called the following error message is shown:
<syntaxhighlight lang="octave">
  octave:1> guide
  warning: the 'guide' function is not yet implemented in Octave

  Please read <http://www.octave.org/missing.html> to learn how you can contribute missing functionality.
  error: 'guide' undefined near line 1 column 1
</syntaxhighlight>

==User interfaces==
Octave comes with an official [[graphical user interface]] (GUI) and an [[integrated development environment]] (IDE) based on [[Qt (software)|Qt]]. It has been available since Octave 3.8,<ref name="auto1">{{Cite web|url=https://www.gnu.org/software/octave/NEWS-3.8.html|title=GNU Octave Version 3.8|website=www.gnu.org}}</ref> and has become the default interface (over the [[command-line interface]]) with the release of Octave 4.0.<ref name="auto"/> 
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.<ref>{{cite web |last=Hageman |first=Steve |date=7 February 2014 |title=GNU Octave hits a high note |url=http://www.edn.com/electronics-blogs/the-practicing-instrumentation-engineer/4428091/GNU-Octave-hits-a-high-note |website=[[EDN (magazine)|EDN]]}}</ref>

Several 3rd-party graphical front-ends have also been developed, like [[Toolbox (software)|ToolboX]] for coding education.

== GUI applications ==
With Octave code, the user can create GUI applications. See [https://octave.org/doc/v7.1.0/GUI-Development.html GUI Development (GNU Octave (version 7.1.0))]. Below are some examples:

Button, edit control, checkbox<syntaxhighlight lang="octave">
# create figure and panel on it
f = figure;
# create a button (default style)
b1 = uicontrol (f, "string", "A Button", "position",[10 10 150 40]);
# create an edit control
e1 = uicontrol (f, "style", "edit", "string", "editable text", "position",[10 60 300 40]);
# create a checkbox
c1 = uicontrol (f, "style", "checkbox", "string", "a checkbox", "position",[10 120 150 40]);
</syntaxhighlight>Textbox<syntaxhighlight lang="octave">
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);
</syntaxhighlight>Listbox with message boxes.<syntaxhighlight lang="octave">
my_options = {"An item", "another", "yet another"};
[sel, ok] = listdlg ("ListString", my_options, "SelectionMode", "Multiple");
if (ok == 1)
  msgbox ("You selected:");
  for i = 1:numel (sel)
    msgbox (sprintf ("\t%s", my_options{sel(i)}));
  endfor
else
  msgbox ("You cancelled.");
endif
</syntaxhighlight>Radiobuttons<syntaxhighlight lang="octave">
# create figure and panel on it
f = figure;
# create a button group
gp = uibuttongroup (f, "Position", [ 0 0.5 1 1])
# create a buttons in the group
b1 = uicontrol (gp, "style", "radiobutton", "string", "Choice 1", "Position", [ 10 150 100 50 ]);
b2 = uicontrol (gp, "style", "radiobutton", "string", "Choice 2", "Position", [ 10 50 100 30 ]);
# create a button not in the group
b3 = uicontrol (f, "style", "radiobutton","string", "Not in the group","Position", [ 10 50 100 50 ]);
</syntaxhighlight>

== Packages ==
Octave also has many packages available.  Those packages are located at Octave-Forge [https://octave.sourceforge.io/packages.php Octave Forge - Packages], or [https://gnu-octave.github.io/packages/symbolic GitHub Octave Packages].  It is also possible for anyone to create and maintain packages.

==Comparison with other similar software==
Alternatives to GNU Octave under an [[free software|open source]] license, other than the aforementioned MATLAB, include [[Scilab]] and [[FreeMat]].<ref name="Trappenberg2010">{{cite book|last=Trappenberg|first=Thomas|title=Fundamentals of Computational Neuroscience|year=2010|publisher=Oxford University Press|isbn=978-0-19-956841-3|page=361}}</ref><ref name="MuhammadZalizniak2011">{{cite book|last1=Muhammad|first1=A|last2=Zalizniak|first2=V|title=Practical Scientific Computing|url=https://archive.org/details/practicalscienti00muha|url-access=limited|year=2011|publisher=[[Woodhead Publishing]]|isbn=978-0-85709-226-7|page=[https://archive.org/details/practicalscienti00muha/page/n11 3]}}</ref><ref name="MegreyMoksness2008">{{cite book|last1=Megrey|first1=Bernard A.|last2=Moksness|first2=Erlend|title=Computers in Fisheries Research|url=https://archive.org/details/computersfisheri00megr|url-access=limited|year=2008|publisher=Springer Science & Business Media|isbn=978-1-4020-8636-6|page=[https://archive.org/details/computersfisheri00megr/page/n351 345]}}</ref><ref name="Kapuno2008">{{cite book|last=Kapuno|first=Raul Raymond|title=Programming for Chemical Engineers Using C, C++, and MATLAB|year=2008|publisher=Jones & Bartlett Publishers|isbn=978-1-934015-09-4|page=365}}</ref> Octave is more compatible with MATLAB than Scilab is,<ref name="Trappenberg2010"/><ref name="Herman2013">{{cite book|last=Herman|first=Russell L.|title=A Course in Mathematical Methods for Physicists|year=2013|publisher=CRC Press|isbn=978-1-4665-8467-9|page=42}}</ref><ref name="WouwerSaucez2014">{{cite book|last1=Wouwer|first1=Alain Vande|last2=Saucez|first2=Philippe|last3=Vilas|first3=Carlos|title=Simulation of ODE/PDE Models with MATLAB, Octave and Scilab: Scientific and Engineering Applications|year=2014|publisher=Springer|isbn=978-3-319-06790-2|pages=114–115}}</ref> and FreeMat has not been updated since June 2013.<ref>{{cite web |title=FreeMat |url=https://freemat.sourceforge.net/ |website=freemat.sourceforge.net |access-date=22 February 2020}}</ref>

Also the [[Julia (programming language)|Julia programming language]] and its plotting capabilities has similarities with GNU Octave.

==See also==
{{Portal|Mathematics|Computer programming|Free and open-source software}}
*[[List of numerical-analysis software]]
*[[Comparison of numerical-analysis software]]
*[[List of statistical packages]]
*[[List of numerical libraries]]

==Notes==
{{notelist}}

==References==
{{Reflist|30em}}

==Further reading==
*{{Citation|last=Hansen|first=Jesper Schmidt|title=GNU Octave. Beginner's Guide|date=June 2011|url=http://www.packtpub.com/gnu-octave-beginners-guide/book|publisher=[[Packt Publishing]]|isbn=978-1-849-51332-6|mode=cs1|access-date=2011-06-26|archive-date=2014-08-02|archive-url=https://web.archive.org/web/20140802023558/http://www.packtpub.com/gnu-octave-beginners-guide/book|url-status=dead}}

==External links==
*{{Official website}}

{{Commons category|GNU Octave}}
{{Wikibooks|Octave Programming Tutorial}}
{{GNU}}
{{Numerical analysis software}}
{{Computer algebra systems}}
{{Statistical software}}
{{Image processing software}}
{{FOSS}}
{{Authority control}}

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