blocks|key|1619874|text|class()函数相当于typeof()。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1619875|您还可以使用isa()检查变量是否为特定类型。如果你想更具体，你可以使用ischar()，isfloat()，iscell()等。|1619876|entityMap|0|LINK|mutability|MUTABLE|url|https://www.mathworks.com/help/matlab/ref/class.html|1|https://www.mathworks.com/help/matlab/ref/isa.html|2|https://www.mathworks.com/help/matlab/ref/ischar.html|3|https://www.mathworks.com/help/matlab/ref/isfloat.html|4|https://www.mathworks.com/help/matlab/ref/iscell.html^0|C|8|0|7|0|0|6|5|1|10|8|2|19|9|3|1J|8|4|0^^$0|@$1|2|3|4|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@$9|10|A|11|1|12]]|E|$]]|$1|F|3|G|5|6|7|13|8|@]|D|@$9|14|A|15|1|16]|$9|17|A|18|1|19]|$9|1A|A|1B|1|1C]|$9|1D|A|1E|1|1F]]|E|$]]|$1|H|3|-4|5|6|7|1G|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]|P|$5|K|L|M|E|$N|Q]]|R|$5|K|L|M|E|$N|S]]|T|$5|K|L|M|E|$N|U]]|V|$5|K|L|M|E|$N|W]]]]

The <a href="https://www.mathworks.com/help/matlab/ref/class.html" rel="nofollow noreferrer">class()</a> function is the equivalent of <code>typeof()</code>.
You can also use <a href="https://www.mathworks.com/help/matlab/ref/isa.html" rel="nofollow noreferrer">isa()</a> to check if a variable is of a particular type. If you want to be even more specific, you can use <a href="https://www.mathworks.com/help/matlab/ref/ischar.html" rel="nofollow noreferrer">ischar()</a>, <a href="https://www.mathworks.com/help/matlab/ref/isfloat.html" rel="nofollow noreferrer">isfloat()</a>, <a href="https://www.mathworks.com/help/matlab/ref/iscell.html" rel="nofollow noreferrer">iscell()</a>, etc.

blocks|key|1405150|text|使用class函数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1405151|>>+b+=+2
b+=
+++++2
>>+a+=+'Hi'
a+=
Hi
>>+class(b)
ans+=
double
>>+class(a)
ans+=
char|code-block|syntax|javascript|1405152|entityMap|0|LINK|mutability|MUTABLE|url|https://www.mathworks.com/help/matlab/ref/class.html^0|2|5|2|5|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Use the <a href="https://www.mathworks.com/help/matlab/ref/class.html" rel="nofollow noreferrer"><code>class</code></a> function:
<pre><code>&gt;&gt; b = 2
b =
 2
&gt;&gt; a = 'Hi'
a =
Hi
&gt;&gt; class(b)
ans =
double
&gt;&gt; class(a)
ans =
char
</code></pre>

blocks|key|1619955|text|另一个相关函数是whos。它将列出给定工作空间中变量的所有信息(尺寸、字节大小、类型)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1619956|>>+a+=+[0+0+7];
>>+whos+a
++Name++++++Size++++++++++++Bytes++Class+++++Attributes

++a+++++++++1x3++++++++++++++++24++double++++++++++++++

>>+b+=+'James+Bond';
>>+whos+b
++Name++++++Size++++++++++++Bytes++Class++++Attributes

++b+++++++++1x10+++++++++++++++20++char+|code-block|syntax|javascript|1619957|entityMap|0|LINK|mutability|MUTABLE|url|http://www.mathworks.com/help/matlab/ref/whos.html^0|8|4|8|4|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Another related function is <a href="http://www.mathworks.com/help/matlab/ref/whos.html" rel="noreferrer"><code>whos</code></a>. It will list all sorts of information (dimensions, byte size, type) for the variables in a given workspace.

<pre><code>&gt;&gt; a = [0 0 7];
&gt;&gt; whos a
 Name Size Bytes Class Attributes

 a 1x3 24 double 

&gt;&gt; b = 'James Bond';
&gt;&gt; whos b
 Name Size Bytes Class Attributes

 b 1x10 20 char 
</code></pre>

blocks|key|1620003|text|由于没有人提到它，MATLAB还具有metaclass函数，该函数返回一个对象，其中包含有关传入实体的各种信息。这些meta.class对象对于继承测试非常有用(通过常见的比较运算符)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1620004|例如：|1620005|>>+metaclass(magic(1))

ans+=+

++class+with+properties:

+++++++++++++++++++++Name:+'double'
++++++++++++++Description:+''
++++++DetailedDescription:+''
+++++++++++++++++++Hidden:+0
+++++++++++++++++++Sealed:+0
+++++++++++++++++Abstract:+0
++++++++++++++Enumeration:+0
++++++++++ConstructOnLoad:+0
+++++++++HandleCompatible:+0
++++++++++InferiorClasses:+{0×1+cell}
++++++++ContainingPackage:+[0×0+meta.package]
+++++RestrictsSubclassing:+0
+++++++++++++PropertyList:+[0×1+meta.property]
+++++++++++++++MethodList:+[272×1+meta.method]
++++++++++++++++EventList:+[0×1+meta.event]
++++EnumerationMemberList:+[0×1+meta.EnumeratedValue]
+++++++++++SuperclassList:+[0×1+meta.class]

>>+?containers.Map+<=+?handle

ans+=

++logical

+++1|code-block|syntax|javascript|1620006|我们可以看到，class(someObj)等同于metaclass(someObj)结果的Name字段。|1620007|entityMap|0|LINK|mutability|MUTABLE|url|https://www.mathworks.com/help/matlab/ref/metaclass.html|1|https://www.mathworks.com/help/matlab/ref/meta.class.html^0|I|9|1M|A|I|9|0|1M|A|1|0|0|0|7|E|O|I|19|4|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@$9|13|A|14|1|15]|$9|16|A|17|1|18]]|E|$]]|$1|F|3|G|5|6|7|19|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|1A|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1B|8|@$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|1I|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]|W|$5|R|S|T|E|$U|X]]]]

Since nobody mentioned it, MATLAB also has the <a href="https://www.mathworks.com/help/matlab/ref/metaclass.html" rel="noreferrer"><code>metaclass</code></a> function, which returns an object with various bits of information about the passed-in entity. These <a href="https://www.mathworks.com/help/matlab/ref/meta.class.html" rel="noreferrer"><code>meta.class</code></a> objects can be useful for tests of inheritance (via common comparison operators).

For example:

<pre class="lang-none prettyprint-override"><code>&gt;&gt; metaclass(magic(1))

ans = 

 class with properties:

 Name: 'double'
 Description: ''
 DetailedDescription: ''
 Hidden: 0
 Sealed: 0
 Abstract: 0
 Enumeration: 0
 ConstructOnLoad: 0
 HandleCompatible: 0
 InferiorClasses: {0×1 cell}
 ContainingPackage: [0×0 meta.package]
 RestrictsSubclassing: 0
 PropertyList: [0×1 meta.property]
 MethodList: [272×1 meta.method]
 EventList: [0×1 meta.event]
 EnumerationMemberList: [0×1 meta.EnumeratedValue]
 SuperclassList: [0×1 meta.class]

&gt;&gt; ?containers.Map &lt;= ?handle

ans =

 logical

 1
</code></pre>

We can see that <code>class(someObj)</code> is equivalent to the <code>Name</code> field of the result of <code>metaclass(someObj)</code>.

Does MATLAB have a function/operator that indicates the type of a variable (similar to the <code>typeof</code> operator in JavaScript)?

How to get the type of a variable in MATLAB

MATLAB是否有一个函数/运算符来指示变量的类型(类似于JavaScript中的typeof运算符)？

问如何在MATLAB中获取变量的类型
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