PHP Math functions is_nan

bool is_nan ( float $input )
ParameterDESCRIPTION
$inputRequired : Number to check.
The output is TRUE if $input is 'not a number', else False.

We can check a input or variable is a number or not by using is_nan function. Note that we can't check a string with this function.
We can check square root of a negative number with is_nan function. Here is a sample code to check.

$v = acos(1.1);
if(is_nan($v)){
echo "this is not a number";
}else{
echo "this is a number";
}
Out put is
this is not a number
You can change the line $v=acos(1.1) with different values of variable $v and see the result.
$v=5.23; // this is a number
$v=4; // this is a number
Your Rating





Post Comment This is for short comments only. Use the forum for more discussions.




HTML MySQL PHP JavaScript ASP Photoshop Articles FORUM . Contact us
©2000-2019 plus2net.com All rights reserved worldwide Privacy Policy Disclaimer