<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ --> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Comments and the Help System (GNU Octave (version 5.1.0))</title> <meta name="description" content="Comments and the Help System (GNU Octave (version 5.1.0))"> <meta name="keywords" content="Comments and the Help System (GNU Octave (version 5.1.0))"> <meta name="resource-type" content="document"> <meta name="distribution" content="global"> <meta name="Generator" content="makeinfo"> <link href="index.html#Top" rel="start" title="Top"> <link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> <link href="Comments.html#Comments" rel="up" title="Comments"> <link href="Data-Types.html#Data-Types" rel="next" title="Data Types"> <link href="Block-Comments.html#Block-Comments" rel="prev" title="Block Comments"> <style type="text/css"> <!-- a.summary-letter {text-decoration: none} blockquote.indentedblock {margin-right: 0em} blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} blockquote.smallquotation {font-size: smaller} div.display {margin-left: 3.2em} div.example {margin-left: 3.2em} div.lisp {margin-left: 3.2em} div.smalldisplay {margin-left: 3.2em} div.smallexample {margin-left: 3.2em} div.smalllisp {margin-left: 3.2em} kbd {font-style: oblique} pre.display {font-family: inherit} pre.format {font-family: inherit} pre.menu-comment {font-family: serif} pre.menu-preformatted {font-family: serif} pre.smalldisplay {font-family: inherit; font-size: smaller} pre.smallexample {font-size: smaller} pre.smallformat {font-family: inherit; font-size: smaller} pre.smalllisp {font-size: smaller} span.nolinebreak {white-space: nowrap} span.roman {font-family: initial; font-weight: normal} span.sansserif {font-family: sans-serif; font-weight: normal} ul.no-bullet {list-style: none} --> </style> <link rel="stylesheet" type="text/css" href="octave.css"> </head> <body lang="en"> <a name="Comments-and-the-Help-System"></a> <div class="header"> <p> Previous: <a href="Block-Comments.html#Block-Comments" accesskey="p" rel="prev">Block Comments</a>, Up: <a href="Comments.html#Comments" accesskey="u" rel="up">Comments</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> </div> <hr> <a name="Comments-and-the-Help-System-1"></a> <h4 class="subsection">2.7.3 Comments and the Help System</h4> <a name="index-documenting-functions"></a> <a name="index-documenting-user-scripts"></a> <a name="index-help_002c-user_002ddefined-functions"></a> <p>The <code>help</code> command (see <a href="Getting-Help.html#Getting-Help">Getting Help</a>) is able to find the first block of comments in a function and return those as a documentation string. This means that the same commands used to get help on built-in functions are available for properly formatted user-defined functions. For example, after defining the function <code>f</code> below, </p> <div class="example"> <pre class="example">function xdot = f (x, t) # usage: f (x, t) # # This function defines the right-hand # side functions for a set of nonlinear # differential equations. r = 0.25; … endfunction </pre></div> <p>the command <kbd>help f</kbd> produces the output </p> <div class="example"> <pre class="example"> usage: f (x, t) This function defines the right-hand side functions for a set of nonlinear differential equations. </pre></div> <p>Although it is possible to put comment lines into keyboard-composed, throw-away Octave programs, it usually isn’t very useful because the purpose of a comment is to help you or another person understand the program at a later time. </p> <p>The <code>help</code> parser currently only recognizes single line comments (see <a href="Single-Line-Comments.html#Single-Line-Comments">Single Line Comments</a>) and not block comments for the initial help text. </p> </body> </html>