How to remove different values ​​from an array in php

In PHP, it is often necessary to retrieve different values ​​from an array, which is very common in scenarios such as data analysis and statistics. Here are two methods to retrieve different values ​​from an array.

Method 1: array_unique function

The array_unique function is a function used in PHP to remove duplicate elements from an array. The return value of this function is a new array containing unique elements in the original array.

The sample code is as follows:

<?php
$arr = array(1, 2, 2, 3, 4, 4, 4, 5);
$newArr = array_unique($arr);
print_r($newArr);
?>

The above code will output the array [1, 2, 3, 4, 5].

It should be noted that the array_unique function requires type conversion for the elements in the array. For example, if the array contains both string type values ​​and integer type values, the array_unique function will convert the integer type value to the string type and then perform the deduplication operation. Therefore, when using the array_unique function, you need to pay attention to the data type of the array elements.

Method 2: Use loop traversal

In addition to using the array_unique function, you can also use loop traversal to retrieve different values ​​​​in the array. The specific method is to use the first element as the benchmark, and then loop through the original array starting from the second element. If an element is found to be the same as the benchmark element, delete the element from the array, otherwise set the element to the new one. base element. This process loops until all elements in the original array have been traversed.

The sample code is as follows:

<?php
$arr = array(1, 2, 2, 3, 4, 4, 4, 5);
for ($i = 0; $i < count($arr); $i++) {
    for ($j = $i + 1; $j < count($arr); $j++) {
        if ($arr[$i] == $arr[$j]) {
            array_splice($arr, $j, 1);
            $j--;
        }
    }
}
print_r($arr);
?>

The above code will output the array [1, 2, 3, 4, 5].

It should be noted that when using loop traversal, if the array is relatively large, it may cause performance problems. Therefore, in practical applications, it is recommended to give priority to using the array_unique function.

Conclusion

In summary, we have introduced two methods to retrieve different values ​​​​in PHP arrays. Whether you use the array_unique function or loop traversal, you can achieve the same effect. For small-scale arrays, it is recommended to use the array_unique function. For large-scale arrays, it is recommended to use loop traversal.

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