is_double

Definition and usage

is_double() function checks whether the variable is of type float.

This function is an alias for is_float() .

Tip: In PHP, floats and doubles are considered to be of the same type. Therefore, the is_double() function is actually just an alias for is_float() function. In actual use, it is more recommended to use the is_float() function because its name describes its function more accurately.

Example

Check whether the variable is float type:

 <?php
$a = 32 ;
echo "a is " . is_double ( $a ) . "<br>" ;

$b = 0 ;
echo "b is " . is_double ( $b ) . "<br>" ;

$c = 32.5 ;
echo "c is " . is_double ( $c ) . "<br>" ;

$d = "32" ;
echo "d is " . is_double ( $d ) . "<br>" ;

$e = true ;
echo "e is " . is_double ( $e ) . "<br>" ;

$f = "null" ;
echo "f is " . is_double ( $f ) . "<br>" ;

$g = 1.e3 ;
echo "g is " . is_double ( $g ) . "<br>" ;
?>

Try it yourself

grammar

 is_double ( variable ) ;