如何去除多维数组中重复的键值数组

Question

我有这个数组，如果它的值与其他数组相同，我想删除它

$appointments = array(
                      array('1','Monday', '5:30 PM'),
                      array('2','Friday', '6:00 PM'),
                      array('3','Monday', '5:30 PM'),
                      array('4','Tuesday', '4:15 PM'),
                      array('5','Wednesday', '8:30 PM'),
                      array('6','Thursday', '1:45 PM')
);

我想要这个结果星期一，时间是显示两次所以我只需要显示一次我使用下面的代码所以请为此提供更好的解决方案

$one_dimension = array_map('serialize', $appointments);
$unique_one_dimension = array_unique($one_dimension);
$unique_multi_dimension = array_map('unserialize', $unique_one_dimension);

echo "<pre>";print_r($unique_multi_dimension);

Answer 1

PHP code demo

<?php

$appointments = array(
                      array('1','Monday', '5:30 PM'),
                      array('2','Friday', '6:00 PM'),
                      array('3','Monday', '5:30 PM'),
                      array('4','Tuesday', '4:15 PM'),
                      array('5','Wednesday', '8:30 PM'),
                      array('6','Thursday', '1:45 PM')
);
//Here we are finding column of week days.


$implodedColumns=  array_map(function($data){
    unset($data[0]);
    return implode(",", array_map('trim', $data));
}, $appointments);
$result=array_unique($implodedColumns); 

array_walk($result, function(&$value,$key){
    $value=  array_merge(array($key),  explode(",", $value));
});

print_r($result); 

输出：

Array
(
    [0] => Array
        (
            [0] => 0
            [1] => Monday
            [2] => 5:30 PM
        )

    [1] => Array
        (
            [0] => 1
            [1] => Friday
            [2] => 6:00 PM
        )

    [3] => Array
        (
            [0] => 3
            [1] => Tuesday
            [2] => 4:15 PM
        )

    [4] => Array
        (
            [0] => 4
            [1] => Wednesday
            [2] => 8:30 PM
        )

    [5] => Array
        (
            [0] => 5
            [1] => Thursday
            [2] => 1:45 PM
        )

)

Answer 2

$one_dimension = array_map('serialize', $appointments);
$unique_one_dimension = array_unique($one_dimension);
$unique_multi_dimension[1] = array_map('unserialize', $unique_one_dimension);

echo "<pre>";print_r($unique_multi_dimension);die;

Answer 3

标准 O(n^2) 通用克隆解决方案：

function array_unique_callback($array, $equalityComparer) {
    $uniqueFiltered = [];
    $keys = array_keys($array);
    for ($i = 0;$i < count($array);$i++) {
         $add = true;
         for ($j = 0;$j < $i;$j++) {
              if ($equalityComparer($array[$keys[$i]], $array[$keys[$j]])) {
                   $add = false;
                   break;
              }
         } 
         if ($add) { 
             $uniqueFiltered[] = $array[$keys[$i]]; 
         }
    }
    return $uniqueFiltered;
}
array_unique_callback($appointments, function ($x,$y) {
     return $x[1] == $y[1] && $x[2] == $y[2];
});

示例： http://sandbox.onlinephpfunctions.com/code/8013c36b78d24f08651b05375d686c9e07c75a49

如果您想要更优化的版本：

function array_unique_callback($array, $comparer) {
   //Comparer is not an equality comparer, it returns negative if $x less than $y, 0 if they are equal and 1 if $x greater than $y
    $keys = array_keys($array);
    uasort($array, $comparer);
    $uniqueFiltered = [];
    for ($i = 0;$i < count($array);$i++) {
        $uniqueFiltered[$keys[$i]] = $array[$keys[$i]]; 
        while ($i < count($array) && $comparer($array[$keys[$i]],$array[$keys[$i+1]]) === 0) { $i++; }
    }
    return $uniqueFiltered;
}

但是，第二个版本需要您决定比较和排序每个元素的方法（这并不总是可行的）。

Answer 4

@Er Nilay Parekh 您可以按照以下概念进行操作：

<?php
  $appointments = array(
                      array('1','Monday', '5:30 PM'),
                      array('2','Friday', '6:00 PM'),
                      array('3','Monday', '5:30 PM'),
                      array('4','Tuesday', '4:15 PM'),
                      array('5','Wednesday', '8:30 PM'),
                      array('6','Thursday', '1:45 PM')
);
$isTimeExist = array();
foreach ($appointments as $key => $value) {
    if(in_array($value[2], $isTimeExist)){
        unset($appointments[$key]);
    }
    $isTimeExist[] = $value[2];
}
echo "<pre>";
print_r(array_values($appointments));