PHP's array_group_by function can group elements in an array based on keys or closure functions, returning an associative array where the key is the group name and the value is an array of elements belonging to the group.
Application of PHP array grouping function in data sorting
Introduction
Data grouping is a common task in data processing that helps us organize and organize data for easier analysis and visualization. The PHP language provides powerful grouping functions that enable us to group data in arrays efficiently.
array_group_by function
array_group_by
function is the main array grouping function in PHP. It groups the elements in an array based on the given key or closure function and returns an associative array where the key is the name of the group and the value is the array of elements belonging to the group.
Syntax
array_group_by(array $array, $key_or_callback): array
- $array: The array to group
- $key_or_callback:Element key name or closure function used as grouping key
Practical case
Suppose we have an array containing student names and grades:
$students = [ ['name' => 'John', 'score' => 85], ['name' => 'Mary', 'score' => 90], ['name' => 'Bob', 'score' => 75], ['name' => 'Sarah', 'score' => 80], ['name' => 'Tom', 'score' => 95], ];
We can use the array_group_by
function to group the array based on students’ grades:
$grouped_students = array_group_by($students, 'score');
This will produce the following grouping results:
[ 85 => [ ['name' => 'John', 'score' => 85] ], 90 => [ ['name' => 'Mary', 'score' => 90] ], 75 => [ ['name' => 'Bob', 'score' => 75] ], 80 => [ ['name' => 'Sarah', 'score' => 80] ], 95 => [ ['name' => 'Tom', 'score' => 95] ], ]
Conclusion
array_group_by
The array_group_by
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