oont-contents/plugins/jetpack/modules/tiled-gallery/math/class-constrained-array-rounding.php
2025-02-08 15:10:23 +01:00

108 lines
3.2 KiB
PHP

<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName
/**
* Lets you round the numeric elements of an array to integers while preserving their sum.
*
* Usage:
*
* Jetpack_Constrained_Array_Rounding::get_rounded_constrained_array( $bound_array )
* if a specific sum doesn't need to be specified for the bound array
*
* Jetpack_Constrained_Array_Rounding::get_rounded_constrained_array( $bound_array, $sum )
* If the sum of $bound_array must equal $sum after rounding.
*
* If $sum is less than the sum of the floor of the elements of the array, the class defaults to using the sum of the array elements.
*/
class Jetpack_Constrained_Array_Rounding {
/**
* Get the rounded constrained array.
*
* @param array $bound_array - the array we're rounding.
* @param int $sum - the sum of the array.
*
* @return array
*/
public static function get_rounded_constrained_array( $bound_array, $sum = false ) {
// Convert associative arrays before working with them and convert them back before returning the values
$keys = array_keys( $bound_array );
$bound_array = array_values( $bound_array );
$bound_array_int = self::get_int_floor_array( $bound_array );
$lower_sum = array_sum( wp_list_pluck( $bound_array_int, 'floor' ) );
if ( ! $sum || ( $sum < $lower_sum ) ) {
// If value of sum is not supplied or is invalid, calculate the sum that the returned array is constrained to match
$sum = array_sum( $bound_array );
}
$diff_sum = $sum - $lower_sum;
self::adjust_constrained_array( $bound_array_int, $diff_sum );
$bound_array_fin = wp_list_pluck( $bound_array_int, 'floor' );
return array_combine( $keys, $bound_array_fin );
}
/**
* Get int floor of array values.
*
* @param array $bound_array - the array we're getting floor values for.
*
* @return array
*/
private static function get_int_floor_array( $bound_array ) {
$bound_array_int_floor = array();
foreach ( $bound_array as $i => $value ) {
$bound_array_int_floor[ $i ] = array(
'floor' => (int) floor( $value ),
'fraction' => $value - floor( $value ),
'index' => $i,
);
}
return $bound_array_int_floor;
}
/**
* Adjust the constrained array.
*
* @param array $bound_array_int - the array we're adjusting.
* @param int $adjustment - how much we're adjusting the array.
*/
private static function adjust_constrained_array( &$bound_array_int, $adjustment ) {
usort( $bound_array_int, array( self::class, 'cmp_desc_fraction' ) );
$start = 0;
$end = $adjustment - 1;
$length = count( $bound_array_int );
for ( $i = $start; $i <= $end; $i++ ) {
++$bound_array_int[ $i % $length ]['floor'];
}
usort( $bound_array_int, array( self::class, 'cmp_asc_index' ) );
}
/**
* Compare fraction values of two arrays.
*
* @param array $a - the first array we're comparing.
* @param array $b - the second array we're comparing.
*
* @return int
*/
private static function cmp_desc_fraction( $a, $b ) {
return $b['fraction'] <=> $a['fraction'];
}
/**
* Compare index values of two arrays.
*
* @param array $a - the first array.
* @param array $b - the second array.
*
* @return int
*/
private static function cmp_asc_index( $a, $b ) {
return $a['index'] <=> $b['index'];
}
}