php string to int

phpCopy<?php  
$variable = "53";
$integer = intval($variable);
echo "The variable $variable has converted to a number and its value is $integer.";  
echo "\n";

$variable = "25.3";
$float = floatval($variable);
echo "The variable $variable has converted to a number and its value is $float.";  
?>

phpCopy<?php  
$variable = "abc";
$integer = (int)$variable;
echo "The variable has converted to a number and its value is $integer.";  
?>