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