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>abs</H1
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><P
> (PHP 3, PHP 4, PHP 5)</P
>abs -- 绝对值</DIV
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><H2
>说明</H2
>number <B
CLASS="methodname"
>abs</B
> ( mixed number )<BR
></BR
><P
> 返回参数 <CODE
CLASS="parameter"
>number</CODE
> 的绝对值。如果参数 <CODE
CLASS="parameter"
>number</CODE
>
是 <A
HREF="language.types.float.html"
><B
CLASS="type"
>float</B
></A
>，则返回的类型也是 <A
HREF="language.types.float.html"
><B
CLASS="type"
>float</B
></A
>，否则返回
<A
HREF="language.types.integer.html"
><B
CLASS="type"
>integer</B
></A
>（因为 <A
HREF="language.types.float.html"
><B
CLASS="type"
>float</B
></A
> 通常比 <A
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><B
CLASS="type"
>integer</B
></A
> 有更大的取值范围）。
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>例 1. <B
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>abs()</B
> </B
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><code><font color="#000000">
<font color="#0000BB"><?php<br />$abs </font><font color="#007700">= </font><font color="#0000BB">abs</font><font color="#007700">(-</font><font color="#0000BB">4.2</font><font color="#007700">); </font><font color="#FF8000">// $abs = 4.2; (double/float)<br /></font><font color="#0000BB">$abs2 </font><font color="#007700">= </font><font color="#0000BB">abs</font><font color="#007700">(</font><font color="#0000BB">5</font><font color="#007700">); </font><font color="#FF8000">// $abs2 = 5; (integer)<br /></font><font color="#0000BB">$abs3 </font><font color="#007700">= </font><font color="#0000BB">abs</font><font color="#007700">(-</font><font color="#0000BB">5</font><font color="#007700">); </font><font color="#FF8000">// $abs3 = 5; (integer)<br /></font><font color="#0000BB">?></font>
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