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   John W. Eaton, David Bateman, Søren Hauberg, Rik Wehbring ({{Release Year}}).
   John W. Eaton, David Bateman, Søren Hauberg, Rik Wehbring ({{Release Year}}).
   GNU Octave version {{Release}} manual: a high-level interactive language for numerical computations.
   GNU Octave version {{Release}} manual: a high-level interactive language for numerical computations.
   URL https://octave.org/doc/v{{Release}}/
   URL https://www.gnu.org/software/octave/doc/v{{Release}}/


A [https://en.wikipedia.org/wiki/BibTeX BibTeX] entry for [https://en.wikipedia.org/wiki/LaTeX LaTeX] users is:
A [https://en.wikipedia.org/wiki/BibTeX BibTeX] entry for [https://en.wikipedia.org/wiki/LaTeX LaTeX] users is:
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     author    = {John W. Eaton and David Bateman and S{\o}ren Hauberg and Rik Wehbring},
     author    = {John W. Eaton and David Bateman and S{\o}ren Hauberg and Rik Wehbring},
     year      = <span>{</span>{{Release Year}}},
     year      = <span>{</span>{{Release Year}}},
     url      = {[https://octave.org/doc/v{{Release}}/ https://octave.org/doc/v{{Release}}/]},
     url      = {https://www.gnu.org/software/octave/doc/v{{Release}}/},
   }
   }


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* After Octave upgrade the GUI does not open / shuts down immediately.
* After Octave upgrade the GUI does not open / shuts down immediately.
** '''Solution:'''
** '''Solution:''' Delete the folder {{path|C:\Users\YOUR_USER_NAME\.config\octave}}
*** Version 5.2.0 and older: Delete the folder {{path|C:\Users\YOUR_USER_NAME\.config\octave}}
*** Version 6.1.0 and newer: Delete the folder {{path|%APPDATA%\octave}}, which generally is located at {{path|C:\Users\YOUR_USER_NAME\AppData\Roaming\octave}}
* Missing/conflicting files.
* Missing/conflicting files.
** '''Solution:''' Remove/Uninstall all existing Octave versions.  Restart the system.  Install GNU Octave again.
** '''Solution:''' Remove/Uninstall all existing Octave versions.  Restart the system.  Install GNU Octave again.
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** '''Solution 1:''' Octave versions prior to version 7.1.0 on MS Windows used VBS scripts to start the program.  You can test whether your system is blocking VBS scripts by doing the following:
** '''Solution 1:''' Octave versions prior to version 7.1.0 on MS Windows used VBS scripts to start the program.  You can test whether your system is blocking VBS scripts by doing the following:
**# Using Notepad or another text editor, create a text file containing only the text: <pre>msgbox("This is a test script, Click OK to close")</pre>
**# Using Notepad or another text editor, create a text file containing only the text: <pre>msgbox("This is a test script, Click OK to close")</pre>
**# Save the file on your Desktop with the name {{Path|testscript.vbs}} (be sure that the editor didn't end it in .txt or .vbs.txt).
**# Save the file on your Desktop with the name {{Path|testscript.vbs}} (be sure that the editor didn't end it in .txt or .vbs.txt)
**# Double click the file.  If scripts can run, a popup window will appear with that message.  
**# Double click the file.  If scripts can run, a popup window will appear with that message.  
**#* If the file opens in notepad or an editor, it means it still ended in .txt.  MS Windows insecurely hides file extensions by default.  To show file extensions follow [https://answers.microsoft.com/en-us/windows/forum/all/in-win10-how-to-show-the-file-extension-for/ed21ff20-cdb3-4263-9c7d-fc6ed125fc82 these instructions at Microsoft.com].
**#* If the file opens in notepad or an editor, it means it still ended in .txt.  MS Windows insecurely hides file extensions by default.  To show file extensions follow [https://answers.microsoft.com/en-us/windows/forum/all/in-win10-how-to-show-the-file-extension-for/ed21ff20-cdb3-4263-9c7d-fc6ed125fc82 these instructions at Microsoft.com].
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==Why is Octave's floating-point computation wrong?==
==Why is Octave's floating-point computation wrong?==


Floating-point arithmetic is an approximation '''in binary''' to arithmetic on real or complex numbers.  Just like you cannot represent 1/3 exactly in decimal arithmetic (0.333333... is only a rough approximation to 1/3 for any finite number of 3s), you cannot represent some fractions like <math>1/10</math> exactly in base 2.  In binary, the representation to one tenth is <math>0.0\overline{0011}_b</math> where the bar indicates that it repeats infinitely (like how <math>1/6 = 0.1\overline{6}_d</math> in decimal).  Because this infinite repetition cannot be represented exactly with a finite number of digits, rounding errors occur for values that appear to be exact in decimal but are in fact approximations in binary, such as for example how 0.3 - 0.2 - 0.1 is not equal to zero.
Floating-point arithmetic is an approximation '''in binary''' to arithmetic on real or complex numbers.  Just like you cannot represent 1/3 exactly in decimal arithmetic (0.333333... is only a rough approximation to 1/3), you cannot represent some fractions like <math>1/10</math> exactly in base 2.  In binary, the representation to one tenth is <math>0.0\overline{0011}_b</math> where the bar indicates that it repeats infinitely (like how <math>1/6 = 0.1\overline{6}_d</math> in decimal).  Because this infinite repetition cannot be represented exactly with a finite number of digits, rounding errors occur for values that appear to be exact in decimal but are in fact approximations in binary, such as for example how 0.3 - 0.2 - 0.1 is not equal to zero.


In addition, some advanced operations are computed by approximation and there is no guarantee for them to be accurate, see [https://en.wikipedia.org/wiki/Rounding#Table-maker.27s_dilemma Table-maker's dilemma] for further references. Their results are system-dependent.
In addition, some advanced operations are computed by approximation and there is no guarantee for them to be accurate, see [https://en.wikipedia.org/wiki/Rounding#Table-maker.27s_dilemma Table-maker's dilemma] for further references. Their results are system-dependent.
Please note that all contributions to Octave may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here.
You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Octave:Copyrights for details). Do not submit copyrighted work without permission!

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