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<is_infinitelcg_value>
Last updated: Mon, 16 Jul 2012

is_nan

(PHP 4 >= 4.2.0, PHP 5)

is_nan -- 判断是否为合法数值

说明

bool is_nan ( float val )

如果 val 为“非数值”，例如 acos(1.01) 的结果，则返回 TRUE。

参见 is_finite() 和 is_infinite()。




<is_infinitelcg_value>
 Last updated: Mon, 16 Jul 2012
 
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