PHP | Ds\Sequence reduce() Function
Last Updated :
22 Aug, 2019
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The Ds\Sequence::reduce() function is an inbuilt function in PHP which is used to reduce the sequence to a single value using a callback function.
Syntax:
php
php
mixed abstract public Ds\Sequence::reduce ( callable $callback [, mixed $initial ] )Parameters: This function accepts two parameters as mentioned above and described below:
- $callback: This parameter holds the function which contains the operation on the elements and store carry. This callback function contains two arguments, carry and value, where carry is the value returned by the function and value is the value of element at the current iteration.
- $initial: This parameter holds the initial value of carry, which can be NULL.
<?php
// Declare new sequence
$seq = new \Ds\Vector([1, 2, 3, 4, 5]);
echo("Sequence Elements\n");
print_r($seq);
// Callback function with reduce function
echo("\nElement after performing operation\n");
var_dump($seq->reduce(function($carry, $element) {
return $carry + $element + 2;
}));
?>
<?php
// Declare new sequence
$seq = new \Ds\Vector([1, 2, 3, 4, 5]);
echo("Sequence Elements\n");
print_r($seq);
// Callback function with reduce function
echo("\nElement after performing operation\n");
var_dump($seq->reduce(function($carry, $element) {
return $carry + $element + 2;
}));
?>
Output:
Program 2:
Sequence Elements Ds\Vector Object ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 ) Element after performing operation int(25)
<?php
// Declare new sequence
$seq = new \Ds\Vector([10, 20, 30, 40, 50]);
echo("Original sequence elements\n");
print_r($seq);
$func_gfg = function($carry, $element) {
return $carry * $element;
};
echo("\nSequence after reducing to single element\n");
// Use reduce() function
var_dump($seq->reduce($func_gfg, 10));
?>
<?php
// Declare new sequence
$seq = new \Ds\Vector([10, 20, 30, 40, 50]);
echo("Original sequence elements\n");
print_r($seq);
$func_gfg = function($carry, $element) {
return $carry * $element;
};
echo("\nSequence after reducing to single element\n");
// Use reduce() function
var_dump($seq->reduce($func_gfg, 10));
?>
Output:
Reference: https://www.php.net/manual/en/ds-sequence.reduce.php
Original sequence elements Ds\Vector Object ( [0] => 10 [1] => 20 [2] => 30 [3] => 40 [4] => 50 ) Sequence after reducing to single element int(120000000)