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<p>
Previous: <a href="Persistent-Variables.html" accesskey="p" rel="prev">Persistent Variables</a>, Up: <a href="Variables.html" accesskey="u" rel="up">Variables</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>
<h3 class="section" id="Status-of-Variables-1"><span>7.3 Status of Variables<a class="copiable-link" href="#Status-of-Variables-1"> ¶</a></span></h3>
<p>When creating simple one-shot programs it can be very convenient to
see which variables are available at the prompt. The function <code class="code">who</code>
and its siblings <code class="code">whos</code> and <code class="code">whos_line_format</code> will show
different information about what is in memory, as the following shows.
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">str = "A random string";
who
-| Variables in the current scope:
-|
-| ans str
</pre></div></div>
<a class="anchor" id="XREFwho"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-who"><span><strong class="def-name">who</strong><a class="copiable-link" href="#index-who"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-who-1"><span><strong class="def-name">who</strong> <code class="def-code-arguments">pattern …</code><a class="copiable-link" href="#index-who-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-who-2"><span><strong class="def-name">who</strong> <code class="def-code-arguments">option pattern …</code><a class="copiable-link" href="#index-who-2"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-who-3"><span><code class="def-type">C =</code> <strong class="def-name">who</strong> <code class="def-code-arguments">(…)</code><a class="copiable-link" href="#index-who-3"> ¶</a></span></dt>
<dd><p>List currently defined variables matching the given patterns.
</p>
<p>Valid pattern syntax is the same as described for the <code class="code">clear</code> command.
If no patterns are supplied, all variables are listed.
</p>
<p>By default, only variables visible in the local scope are displayed.
</p>
<p>The following are valid options, but may not be combined.
</p>
<dl class="table">
<dt><code class="code">global</code></dt>
<dd><p>List variables in the global scope rather than the current scope.
</p>
</dd>
<dt><code class="code">-regexp</code></dt>
<dd><p>The patterns are considered to be regular expressions when matching the
variables to display. The same pattern syntax accepted by the <code class="code">regexp</code>
function is used.
</p>
</dd>
<dt><code class="code">-file</code></dt>
<dd><p>The next argument is treated as a filename. All variables found within the
specified file are listed. No patterns are accepted when reading variables
from a file.
</p></dd>
</dl>
<p>If called as a function, return a cell array of defined variable names
matching the given patterns.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFwhos">whos</a>, <a class="ref" href="Global-Variables.html#XREFisglobal">isglobal</a>, <a class="ref" href="Variables.html#XREFisvarname">isvarname</a>, <a class="ref" href="#XREFexist">exist</a>, <a class="ref" href="Searching-and-Replacing-in-Strings.html#XREFregexp">regexp</a>.
</p></dd></dl>
<a class="anchor" id="XREFwhos"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-whos"><span><strong class="def-name">whos</strong><a class="copiable-link" href="#index-whos"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-whos-1"><span><strong class="def-name">whos</strong> <code class="def-code-arguments">pattern …</code><a class="copiable-link" href="#index-whos-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-whos-2"><span><strong class="def-name">whos</strong> <code class="def-code-arguments">option pattern …</code><a class="copiable-link" href="#index-whos-2"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-whos-3"><span><code class="def-type">S =</code> <strong class="def-name">whos</strong> <code class="def-code-arguments">("pattern", …)</code><a class="copiable-link" href="#index-whos-3"> ¶</a></span></dt>
<dd><p>Provide detailed information on currently defined variables matching the
given patterns.
</p>
<p>Options and pattern syntax are the same as for the <code class="code">who</code> command.
</p>
<p>Extended information about each variable is summarized in a table with the
following default entries.
</p>
<dl class="table">
<dt>Attr</dt>
<dd><p>Attributes of the listed variable. Possible attributes are:
</p>
<dl class="table">
<dt>blank</dt>
<dd><p>Variable in local scope
</p>
</dd>
<dt><code class="code">c</code></dt>
<dd><p>Variable of complex type.
</p>
</dd>
<dt><code class="code">f</code></dt>
<dd><p>Formal parameter (function argument).
</p>
</dd>
<dt><code class="code">g</code></dt>
<dd><p>Variable with global scope.
</p>
</dd>
<dt><code class="code">p</code></dt>
<dd><p>Persistent variable.
</p></dd>
</dl>
</dd>
<dt>Name</dt>
<dd><p>The name of the variable.
</p>
</dd>
<dt>Size</dt>
<dd><p>The logical size of the variable. A scalar is 1x1, a vector is
1xN or Nx1, a 2-D matrix is MxN.
</p>
</dd>
<dt>Bytes</dt>
<dd><p>The amount of memory currently used to store the variable.
</p>
</dd>
<dt>Class</dt>
<dd><p>The class of the variable. Examples include double, single, char, uint16,
cell, and struct.
</p></dd>
</dl>
<p>The table can be customized to display more or less information through
the function <code class="code">whos_line_format</code>.
</p>
<p>If <code class="code">whos</code> is called as a function, return a struct array of defined
variable names matching the given patterns. Fields in the structure
describing each variable are: name, size, bytes, class, global, sparse,
complex, nesting, persistent.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFwho">who</a>, <a class="ref" href="#XREFwhos_005fline_005fformat">whos_line_format</a>.
</p></dd></dl>
<a class="anchor" id="XREFwhos_005fline_005fformat"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-whos_005fline_005fformat"><span><code class="def-type"><var class="var">val</var> =</code> <strong class="def-name">whos_line_format</strong> <code class="def-code-arguments">()</code><a class="copiable-link" href="#index-whos_005fline_005fformat"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-whos_005fline_005fformat-1"><span><code class="def-type"><var class="var">old_val</var> =</code> <strong class="def-name">whos_line_format</strong> <code class="def-code-arguments">(<var class="var">new_val</var>)</code><a class="copiable-link" href="#index-whos_005fline_005fformat-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-whos_005fline_005fformat-2"><span><code class="def-type"><var class="var">old_val</var> =</code> <strong class="def-name">whos_line_format</strong> <code class="def-code-arguments">(<var class="var">new_val</var>, "local")</code><a class="copiable-link" href="#index-whos_005fline_005fformat-2"> ¶</a></span></dt>
<dd><p>Query or set the format string used by the command <code class="code">whos</code>.
</p>
<p>A full format string is:
</p>
<div class="example smallexample">
<pre class="example-preformatted">%[modifier]<command>[:width[:left-min[:balance]]];
</pre></div>
<p>The following command sequences are available:
</p>
<dl class="table">
<dt><code class="code">%a</code></dt>
<dd><p>Prints attributes of variables (c=complex, s=sparse, f=formal parameter,
g=global, p=persistent).
</p>
</dd>
<dt><code class="code">%b</code></dt>
<dd><p>Prints number of bytes occupied by variables.
</p>
</dd>
<dt><code class="code">%c</code></dt>
<dd><p>Prints class names of variables.
</p>
</dd>
<dt><code class="code">%e</code></dt>
<dd><p>Prints elements held by variables.
</p>
</dd>
<dt><code class="code">%n</code></dt>
<dd><p>Prints variable names.
</p>
</dd>
<dt><code class="code">%s</code></dt>
<dd><p>Prints dimensions of variables.
</p>
</dd>
<dt><code class="code">%t</code></dt>
<dd><p>Prints type names of variables.
</p></dd>
</dl>
<p>Every command may also have an alignment modifier:
</p>
<dl class="table">
<dt><code class="code">l</code></dt>
<dd><p>Left alignment.
</p>
</dd>
<dt><code class="code">r</code></dt>
<dd><p>Right alignment (default).
</p>
</dd>
<dt><code class="code">c</code></dt>
<dd><p>Column-aligned (only applicable to command %s).
</p></dd>
</dl>
<p>The <code class="code">width</code> parameter is a positive integer specifying the minimum
number of columns used for printing. No maximum is needed as the field will
auto-expand as required.
</p>
<p>The parameters <code class="code">left-min</code> and <code class="code">balance</code> are only available when
the column-aligned modifier is used with the command ‘<samp class="samp">%s</samp>’.
<code class="code">balance</code> specifies the column number within the field width which
will be aligned between entries. Numbering starts from 0 which indicates
the leftmost column. <code class="code">left-min</code> specifies the minimum field width to
the left of the specified balance column.
</p>
<p>The default format is:
</p>
<div class="example">
<pre class="example-preformatted">" %la:5; %ln:6; %cs:16:6:1; %rb:12; %lc:-1;\n"
</pre></div>
<p>When called from inside a function with the <code class="code">"local"</code> option, the
variable is changed locally for the function and any subroutines it calls.
The original variable value is restored when exiting the function.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFwhos">whos</a>.
</p></dd></dl>
<p>Instead of displaying which variables are in memory, it is possible
to determine if a given variable is available. That way it is possible
to alter the behavior of a program depending on the existence of a
variable. The following example illustrates this.
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">if (! exist ("meaning", "var"))
disp ("The program has no 'meaning'");
endif
</pre></div></div>
<a class="anchor" id="XREFexist"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-exist"><span><code class="def-type"><var class="var">c</var> =</code> <strong class="def-name">exist</strong> <code class="def-code-arguments">(<var class="var">name</var>)</code><a class="copiable-link" href="#index-exist"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-exist-1"><span><code class="def-type"><var class="var">c</var> =</code> <strong class="def-name">exist</strong> <code class="def-code-arguments">(<var class="var">name</var>, <var class="var">type</var>)</code><a class="copiable-link" href="#index-exist-1"> ¶</a></span></dt>
<dd><p>Check for the existence of <var class="var">name</var> as a variable, function, file, directory,
or class.
</p>
<p>The return code <var class="var">c</var> is one of
</p>
<dl class="table">
<dt>1</dt>
<dd><p><var class="var">name</var> is a variable.
</p>
</dd>
<dt>2</dt>
<dd><p><var class="var">name</var> is an absolute filename, an ordinary file in Octave’s <code class="code">path</code>,
or (after appending ‘<samp class="samp">.m</samp>’) a function file in Octave’s <code class="code">path</code>.
</p>
</dd>
<dt>3</dt>
<dd><p><var class="var">name</var> is a ‘<samp class="samp">.oct</samp>’ or ‘<samp class="samp">.mex</samp>’ file in Octave’s <code class="code">path</code>.
</p>
</dd>
<dt>5</dt>
<dd><p><var class="var">name</var> is a built-in function.
</p>
</dd>
<dt>7</dt>
<dd><p><var class="var">name</var> is a directory.
</p>
</dd>
<dt>8</dt>
<dd><p><var class="var">name</var> is a classdef class.
</p>
</dd>
<dt>103</dt>
<dd><p><var class="var">name</var> is a function not associated with a file (entered on the command
line).
</p>
</dd>
<dt>0</dt>
<dd><p><var class="var">name</var> does not exist.
</p></dd>
</dl>
<p>If the optional argument <var class="var">type</var> is supplied, check only for symbols of the
specified type. Valid types are
</p>
<dl class="table">
<dt><code class="code">"var"</code></dt>
<dd><p>Check only for variables.
</p>
</dd>
<dt><code class="code">"builtin"</code></dt>
<dd><p>Check only for built-in functions.
</p>
</dd>
<dt><code class="code">"dir"</code></dt>
<dd><p>Check only for directories.
</p>
</dd>
<dt><code class="code">"file"</code></dt>
<dd><p>Check only for files and directories.
</p>
</dd>
<dt><code class="code">"class"</code></dt>
<dd><p>Check only for classdef classes.
</p></dd>
</dl>
<p>If no type is given, and there are multiple possible matches for name,
<code class="code">exist</code> will return a code according to the following priority list:
variable, built-in function, oct-file, directory, file, class.
</p>
<p><code class="code">exist</code> returns 2 if a regular file called <var class="var">name</var> is present in
Octave’s search path. For information about other types of files not on the
search path use some combination of the functions <code class="code">file_in_path</code> and
<code class="code">stat</code> instead.
</p>
<p>Programming Note: If <var class="var">name</var> is implemented by a buggy .oct/.mex file,
calling <var class="var">exist</var> may cause Octave to crash. To maintain high performance,
Octave trusts .oct/.mex files instead of sandboxing them.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="Manipulating-the-Load-Path.html#XREFfile_005fin_005floadpath">file_in_loadpath</a>, <a class="ref" href="Filesystem-Utilities.html#XREFfile_005fin_005fpath">file_in_path</a>, <a class="ref" href="Manipulating-the-Load-Path.html#XREFdir_005fin_005floadpath">dir_in_loadpath</a>, <a class="ref" href="Filesystem-Utilities.html#XREFstat">stat</a>.
</p></dd></dl>
<p>Usually Octave will manage the memory, but sometimes it can be practical
to remove variables from memory manually. This is usually needed when
working with large variables that fill a substantial part of the memory.
On a computer that uses the IEEE 754 floating point format, the following
program allocates a matrix that requires around 128 MB memory.
</p>
<div class="example">
<pre class="example-preformatted">large_matrix = zeros (4000, 4000);
</pre></div>
<p>Since having this variable in memory might slow down other computations,
it can be necessary to remove it manually from memory. The <code class="code">clear</code>
or <code class="code">clearvars</code> functions do this.
</p>
<a class="anchor" id="XREFclear"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-clear"><span><strong class="def-name">clear</strong><a class="copiable-link" href="#index-clear"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clear-1"><span><strong class="def-name">clear</strong> <code class="def-code-arguments"><var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clear-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clear-2"><span><strong class="def-name">clear</strong> <code class="def-code-arguments"><var class="var">options</var> <var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clear-2"> ¶</a></span></dt>
<dd><p>Delete the names matching the given <var class="var">pattern</var>s thereby freeing memory.
</p>
<p>The <var class="var">pattern</var> may contain the following special characters:
</p>
<dl class="table">
<dt><code class="code">?</code></dt>
<dd><p>Match any single character.
</p>
</dd>
<dt><code class="code">*</code></dt>
<dd><p>Match zero or more characters.
</p>
</dd>
<dt><code class="code">[ <var class="var">list</var> ]</code></dt>
<dd><p>Match the list of characters specified by <var class="var">list</var>. If the first character
is <code class="code">!</code> or <code class="code">^</code>, match all characters except those specified by
<var class="var">list</var>. For example, the pattern <code class="code">[a-zA-Z]</code> will match all lowercase
and uppercase alphabetic characters. On Windows, square brackets are matched
literally and are not used to group characters.
</p></dd>
</dl>
<p>For example, the command
</p>
<div class="example">
<pre class="example-preformatted">clear foo b*r
</pre></div>
<p>clears the name <code class="code">foo</code> and all names that begin with the letter ‘<samp class="samp">b</samp>’
and end with the letter ‘<samp class="samp">r</samp>’.
</p>
<p>If <code class="code">clear</code> is called without any arguments, all user-defined variables
are cleared from the current workspace (i.e., local variables). Any global
variables present will no longer be visible in the current workspace, but they
will continue to exist in the global workspace. Functions are unaffected by
this form of <code class="code">clear</code>.
</p>
<p>The following options are available in both long and short form
</p>
<dl class="table">
<dt><code class="code">all, -all, -a</code></dt>
<dd><p>Clear all local and global user-defined variables, and all functions from the
symbol table.
</p>
</dd>
<dt><code class="code">-exclusive, -x</code></dt>
<dd><p>Clear variables that do <strong class="strong">not</strong> match the following pattern.
</p>
</dd>
<dt><code class="code">functions, -functions, -f</code></dt>
<dd><p>Clear function names from the function symbol table. Persistent variables
will be re-initialized to their default value unless the function has been
locked in memory with <code class="code">mlock</code>.
</p>
</dd>
<dt><code class="code">global, -global, -g</code></dt>
<dd><p>Clear global variable names.
</p>
</dd>
<dt><code class="code">variables, -variables, -v</code></dt>
<dd><p>Clear local variable names.
</p>
</dd>
<dt><code class="code">classes, -classes, -c</code></dt>
<dd><p>Clear the class structure table and all objects.
</p>
</dd>
<dt><code class="code">-regexp, -r</code></dt>
<dd><p>The <var class="var">pattern</var> arguments are treated as regular expressions and any matches
will be cleared.
</p></dd>
</dl>
<p>With the exception of <samp class="option">-exclusive</samp> and <samp class="option">-regexp</samp>, all long
options can be used without the dash as well. Note that, aside from
<samp class="option">-exclusive</samp>, only one other option may appear. All options must
appear before any patterns.
</p>
<p>Programming Notes: The command <code class="code">clear <var class="var">name</var></code> only clears the variable
<var class="var">name</var> when both a variable and a (shadowed) function named <var class="var">name</var>
are currently defined. For example, suppose you have defined a function
<code class="code">foo</code>, and then hidden it by performing the assignment <code class="code">foo = 2</code>.
Executing the command <code class="code">clear foo</code> once will clear the variable
definition and restore the definition of <code class="code">foo</code> as a function.
Executing <code class="code">clear foo</code> a second time will clear the function definition.
</p>
<p>When a local variable name, which is linked to a global variable, is cleared
only the local copy of the variable is removed. The global copy is untouched
and can be restored with <code class="code">global <var class="var">global_varname</var></code>. Conversely,
<code class="code">clear -g <var class="var">global_varname</var></code> will remove both the local and global
variables.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFclearvars">clearvars</a>, <a class="ref" href="#XREFwho">who</a>, <a class="ref" href="#XREFwhos">whos</a>, <a class="ref" href="#XREFexist">exist</a>, <a class="ref" href="Function-Locking.html#XREFmlock">mlock</a>.
</p></dd></dl>
<a class="anchor" id="XREFclearvars"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-clearvars"><span><strong class="def-name">clearvars</strong><a class="copiable-link" href="#index-clearvars"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clearvars-1"><span><strong class="def-name">clearvars</strong> <code class="def-code-arguments"><var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clearvars-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clearvars-2"><span><strong class="def-name">clearvars</strong> <code class="def-code-arguments">-regexp <var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clearvars-2"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clearvars-3"><span><strong class="def-name">clearvars</strong> <code class="def-code-arguments">… -except <var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clearvars-3"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clearvars-4"><span><strong class="def-name">clearvars</strong> <code class="def-code-arguments">… -except -regexp <var class="var">pattern</var> …</code><a class="copiable-link" href="#index-clearvars-4"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-clearvars-5"><span><strong class="def-name">clearvars</strong> <code class="def-code-arguments">-global …</code><a class="copiable-link" href="#index-clearvars-5"> ¶</a></span></dt>
<dd><p>Delete the variables matching the given <var class="var">pattern</var>s from memory.
</p>
<p>The <var class="var">pattern</var> may contain the following special characters:
</p>
<dl class="table">
<dt><code class="code">?</code></dt>
<dd><p>Match any single character.
</p>
</dd>
<dt><code class="code">*</code></dt>
<dd><p>Match zero or more characters.
</p>
</dd>
<dt><code class="code">[ <var class="var">list</var> ]</code></dt>
<dd><p>Match the list of characters specified by <var class="var">list</var>. If the first
character is <code class="code">!</code> or <code class="code">^</code>, match all characters except those
specified by <var class="var">list</var>. For example, the pattern <code class="code">[a-zA-Z]</code> will
match all lowercase and uppercase alphabetic characters.
</p></dd>
</dl>
<p>If the <samp class="option">-regexp</samp> option is given then subsequent patterns are treated
as regular expressions and any matches will be cleared.
</p>
<p>If the <samp class="option">-except</samp> option is given then subsequent patterns select
variables that will <strong class="strong">not</strong> be cleared.
</p>
<p>If the <samp class="option">-global</samp> option is given then all patterns will be applied
to global variables rather than local variables.
</p>
<p>When called with no arguments, <code class="code">clearvars</code> deletes all local variables.
</p>
<p>Example Code:
</p>
<p>Clear all variables starting with <code class="code">'x'</code> and the specific variable
<code class="code">"foobar"</code>
</p>
<div class="example">
<pre class="example-preformatted">clearvars x* foobar
</pre></div>
<p>Clear the specific variable <code class="code">"foobar"</code> and use regular expressions to
clear all variables starting with <code class="code">'x'</code> or <code class="code">'y'</code>.
</p>
<div class="example">
<pre class="example-preformatted">clearvars foobar -regexp ^x ^y
</pre></div>
<p>Clear all variables except for <code class="code">"foobar"</code>
</p>
<div class="example">
<pre class="example-preformatted">clearvars -except foobar
</pre></div>
<p>Clear all variables beginning with <code class="code">"foo"</code>, except for those ending
in <code class="code">"bar"</code>
</p>
<div class="example">
<pre class="example-preformatted">clearvars foo* -except -regexp bar$
</pre></div>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFclear">clear</a>, <a class="ref" href="#XREFwho">who</a>, <a class="ref" href="#XREFwhos">whos</a>, <a class="ref" href="#XREFexist">exist</a>.
</p></dd></dl>
<a class="anchor" id="XREFpack"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-pack"><span><strong class="def-name">pack</strong> <code class="def-code-arguments">()</code><a class="copiable-link" href="#index-pack"> ¶</a></span></dt>
<dd><p>Consolidate workspace memory in <small class="sc">MATLAB</small>.
</p>
<p>This function is provided for compatibility, but does nothing in Octave.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFclear">clear</a>.
</p></dd></dl>
<p>Information about a function or variable such as its location in the
file system can also be acquired from within Octave. This is usually
only useful during development of programs, and not within a program.
</p>
<a class="anchor" id="XREFtype"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-type"><span><strong class="def-name">type</strong> <code class="def-code-arguments"><var class="var">name</var> …</code><a class="copiable-link" href="#index-type"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-type-1"><span><strong class="def-name">type</strong> <code class="def-code-arguments">-q <var class="var">name</var> …</code><a class="copiable-link" href="#index-type-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-type-2"><span><code class="def-type">text =</code> <strong class="def-name">type</strong> <code class="def-code-arguments">("<var class="var">name</var>", …)</code><a class="copiable-link" href="#index-type-2"> ¶</a></span></dt>
<dd><p>Display the contents of <var class="var">name</var> which may be a file, function (m-file),
variable, operator, or keyword.
</p>
<p><code class="code">type</code> normally prepends a header line describing the category of
<var class="var">name</var> such as function or variable; The <samp class="option">-q</samp> option suppresses
this behavior.
</p>
<p>If no output variable is used the contents are displayed on screen.
Otherwise, a cell array of strings is returned, where each element
corresponds to the contents of each requested function.
</p></dd></dl>
<a class="anchor" id="XREFwhich"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-which"><span><strong class="def-name">which</strong> <code class="def-code-arguments"><var class="var">name</var> …</code><a class="copiable-link" href="#index-which"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-which-1"><span><code class="def-type">[<var class="var">str</var>, …] =</code> <strong class="def-name">which</strong> <code class="def-code-arguments">('<var class="var">name</var>', …)</code><a class="copiable-link" href="#index-which-1"> ¶</a></span></dt>
<dd><p>Display the type of each <var class="var">name</var>.
</p>
<p>If <var class="var">name</var> is defined from a function file, the full name of the file is
also displayed.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="Getting-Help.html#XREFhelp">help</a>, <a class="ref" href="Getting-Help.html#XREFlookfor">lookfor</a>.
</p></dd></dl>
<a class="anchor" id="XREFwhat"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-what"><span><strong class="def-name">what</strong><a class="copiable-link" href="#index-what"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-what-1"><span><strong class="def-name">what</strong> <code class="def-code-arguments"><var class="var">dir</var></code><a class="copiable-link" href="#index-what-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-what-2"><span><code class="def-type">w =</code> <strong class="def-name">what</strong> <code class="def-code-arguments">(<var class="var">dir</var>)</code><a class="copiable-link" href="#index-what-2"> ¶</a></span></dt>
<dd><p>List the Octave specific files in directory <var class="var">dir</var>.
</p>
<p>If <var class="var">dir</var> is not specified then the current directory is used.
</p>
<p>If a return argument is requested, the files found are returned in the
structure <var class="var">w</var>. The structure contains the following fields:
</p>
<dl class="table">
<dt>path</dt>
<dd><p>Full path to directory <var class="var">dir</var>
</p>
</dd>
<dt>m</dt>
<dd><p>Cell array of m-files
</p>
</dd>
<dt>mat</dt>
<dd><p>Cell array of mat files
</p>
</dd>
<dt>mex</dt>
<dd><p>Cell array of mex files
</p>
</dd>
<dt>oct</dt>
<dd><p>Cell array of oct files
</p>
</dd>
<dt>mdl</dt>
<dd><p>Cell array of mdl files
</p>
</dd>
<dt>slx</dt>
<dd><p>Cell array of slx files
</p>
</dd>
<dt>p</dt>
<dd><p>Cell array of p-files
</p>
</dd>
<dt>classes</dt>
<dd><p>Cell array of class directories (<samp class="file">@<var class="var">classname</var>/</samp>)
</p>
</dd>
<dt>packages</dt>
<dd><p>Cell array of package directories (<samp class="file">+<var class="var">pkgname</var>/</samp>)
</p></dd>
</dl>
<p>Compatibility Note: Octave does not support mdl, slx, and p files.
<code class="code">what</code> will always return an empty list for these categories.
</p>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFwhich">which</a>, <a class="ref" href="Current-Working-Directory.html#XREFls">ls</a>, <a class="ref" href="#XREFexist">exist</a>.
</p></dd></dl>
</div>
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