is_nan

名称:is_nan

分类:数学

所属语言:php

一句话介绍:判断是否为合法数值。

实例

<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">echo</span> <span class="token function">is_nan</span><span class="token punctuation">(</span><span class="token number">200</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">is_nan</span><span class="token punctuation">(</span><span class="token function">acos</span><span class="token punctuation">(</span><span class="token number">1.01</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

亲自试一试