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# Find if variable is divisible by 2

Questions:

How do I figure out if a variable is divisible by 2? Furthermore I need do a function if it is and do a different function if it is not.

Use modulus:

``````// Will evaluate to true if the variable is divisible by 2
variable % 2 === 0
``````

Questions:

Seriously, there’s no jQuery plugin for odd/even checks?

Well, not anymore – releasing “Oven” a jQuery plugin under the MIT license to test if a given number is Odd/Even.

Source code is also available at http://jsfiddle.net/7HQNG/

Test-suites are available at http://jsfiddle.net/zeuRV/

``````(function() {
/*
* isEven(n)
* @args number n
* @return boolean returns whether the given number is even
*/
jQuery.isEven = function(number) {
return number % 2 == 0;
};

/* isOdd(n)
* @args number n
* @return boolean returns whether the given number is odd
*/
jQuery.isOdd = function(number) {
return !jQuery.isEven(number);
};
})();​
``````

Questions:

You don’t need jQuery. Just use JavaScript’s Modulo operator.

Questions:

You can use the modulus operator like this, no need for jQuery. Just replace the `alerts` with your code.

``````var x = 2;
if (x % 2 == 0)
{
}
else
{
}
``````

Questions:

You can do it in a better way (up to 50 % faster than modulo operator):

odd: x & 1
even: !(x & 1)

Reference: High Performance JavaScript, 8. ->Bitwise Operators

Questions:

You can also:

``````if (x & 1)
itsOdd();
else
itsEven();
``````

Questions:
``````var x = 2;
x % 2 ? oddFunction() : evenFunction();
``````

Questions:

array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

array.each { |x| puts x if x % 2 == 0 }

# ruby 😀

2
4
6
8
10

Questions:

``````var isEven = function(deep) {

if (deep % 2 === 0) {
return true;
}
else {
return false;
}
};
isEven(44);
``````

Please Note: It will return true, if the entered number is even otherwise false.

Questions:
``````x % 2 == 0
Remember to declare your variables too, so obviously that line couldn’t be written standalone. 🙂 Usually used as an `if` statement. Hope this helps.