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<div class="section" id="Command-Syntax-and-Function-Syntax">
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<p>
Next: <a href="Organization-of-Functions.html" accesskey="n" rel="next">Organization of Functions Distributed with Octave</a>, Previous: <a href="Function-Handles-and-Anonymous-Functions.html" accesskey="p" rel="prev">Function Handles and Anonymous Functions</a>, Up: <a href="Functions-and-Scripts.html" accesskey="u" rel="up">Functions and Scripts</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
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<hr>
<span id="Command-Syntax-and-Function-Syntax-1"></span><h3 class="section">11.13 Command Syntax and Function Syntax</h3>
<span id="index-commands-functions"></span>
<p>Additionally to the function syntax described above (i.e., calling a function
like <code>fun (arg1, arg2, …)</code>), a function can be called using command
syntax (for example, calling a function like <code>fun arg1 arg2 …</code>). In
that case, all arguments are passed to the function as strings. For example,
</p>
<div class="example">
<pre class="example">my_command hello world
</pre></div>
<p>is equivalent to
</p>
<div class="example">
<pre class="example">my_command ("hello", "world")
</pre></div>
<p>The general form of a command call is
</p>
<div class="example">
<pre class="example">cmdname arg1 arg2 …
</pre></div>
<p>which translates directly to
</p>
<div class="example">
<pre class="example">cmdname ("arg1", "arg2", …)
</pre></div>
<p>If an argument including spaces should be passed to a function in command
syntax, (double-)quotes can be used. For example,
</p>
<div class="example">
<pre class="example">my_command "first argument" "second argument"
</pre></div>
<p>is equivalent to
</p>
<div class="example">
<pre class="example">my_command ("first argument", "second argument")
</pre></div>
<p>Any function can be used as a command if it accepts string input arguments.
For example:
</p>
<div class="example">
<pre class="example">toupper lower_case_arg
⇒ ans = LOWER_CASE_ARG
</pre></div>
<p>Since the arguments are passed as strings to the corresponding function, it is
not possible to pass input arguments that are stored in variables. In that
case, a command must be called using the function syntax. For example:
</p>
<div class="example">
<pre class="example">strvar = "hello world";
toupper strvar
⇒ ans = STRVAR
toupper (strvar)
⇒ ans = HELLO WORLD
</pre></div>
<p>Additionally, the return values of functions cannot be assigned to variables
using the command syntax. Only the first return argument is assigned to the
built-in variable <code>ans</code>. If the output argument of a command should be
assigned to a variable, or multiple output arguments of a function should be
returned, the function syntax must be used.
</p>
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Next: <a href="Organization-of-Functions.html">Organization of Functions Distributed with Octave</a>, Previous: <a href="Function-Handles-and-Anonymous-Functions.html">Function Handles and Anonymous Functions</a>, Up: <a href="Functions-and-Scripts.html">Functions and Scripts</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
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