4696

How to counting varians data from array?

Question:

I have an array like this

$arr = array(1,2,1,3,2,4);

How to count total of variant data from that array ?

example :

$arr = array(1,2,1,3,2,4); <blockquote>

total = 4

</blockquote>

Answer1:

You can flip the array, and check its length:

echo count(array_flip($arr));

This works because an array index must be unique, so you end up with one element for every unique item in the original array:

<a href="http://php.net/manual/en/function.array-flip.php" rel="nofollow">http://php.net/manual/en/function.array-flip.php</a>

<blockquote>

If a value has several occurrences, the latest key will be used as its value, and all others will be lost.

</blockquote>

This is (was?) somewhat faster than array_unique, but unless you are calling this a LOT, array_unique is a lot more descriptive, so probably the better option

Answer2:

If you are trying to count the unique values in an array, this is very straightforward and rather obvious:

echo count(array_unique($arr));

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