converting from float to Int in php -

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• explain php output 1 answer

i trying understand converting float int in php ,and came across following code:

echo (int) ( (0.1+0.7) * 10 ); // echoes 7! 

my question why echo 7 instead of 8? logic behind it?

here:

$var = (int) $othervar; 

i guess:

$var = int($othervar); 

would work too. not!

gettype() tell type, get_class() tell class of object, both return strings, get_class() returns current class if no argument or null provided, if provide non-object get_class() it's sort of error.

these functions example of how bad php, gettype() , get_class(), fun fact, because have play "guess has underscore" have is_a() (function, expects $var , "typename") , instanceof (operator).

instead is:

$var = intval($othervar); 

and there's floatval, whole lot have val after them! more php sillyness.

note that:

$var = (string) $othervar; 

invokes $othervar's __tostring() method, there isn't __toint() method, strings.

hope helps.

addendum:

integers truncated, hence 7.

other addendum:

if want more controlled conversion can use round() works 1 expect, floor() (rounds down, 7 less x less 8 floors 7, -3 less x less-2 floors -3) , ceil() rounds (7 less x less 8 ceils 8, -3 less x less -2 ceils -2)

this question exact copy of:

why on earth php convert result of (int) ((0.1+0.7)*10) 7, not 8?

even example!