array_count_values: counting the frequency of elements inside array

Frequency of values inside an array

array_count_values ($input_array )

Parameter	DESCRIPTION
$input_array	Required : Input array of which frequency of values to be calculated

We can count the number of time elements are present inside an array by using array_count_values function in php. This function returns another array which stores the values ( or elements ) of the input array and its frequency or the number of occurrence of the value.

This function array_count_values works similar to group by sql query where we collect unique records with number of occurrence in a table

Here is the syntax of this function.


$result= array_count_values ($input_array)

Let us try one example to understand how this works.


$a1=array("first", "second", "third","fourth","fifth","second","third");
$new_array=array_count_values($a1);

while (list ($key, $val) = each ($new_array)) {
echo "$key -> $val <br>";
}

The output of above code will be

first -> 1
second -> 2
third -> 2
fourth -> 1
fifth -> 1