排序和過濾多維數組

Question

我需要用這個多維數組抓住每個國家的老年人

$arrayPersonas = array(
    array('id'=> "0AB239", 'country' => 1, 'firstname' => "Ernest"  , 'surname' => "Austin", 'age' => 30),
    array('id'=> "12A179", 'country' => 0, 'firstname' => "Frances", 'surname' => "Poole", 'age' => 23),
    array('id'=> "1A90B9", 'country' => 1, 'firstname' => "Jacob", 'surname' => "Matthews", 'age' => 30),
    array('id'=> "227FF9", 'country' => 2, 'firstname' => "Mina", 'surname' => "Day", 'age' => 30),
    array('id'=> "2A6F39", 'country' => 3, 'firstname' => "Earl", 'surname' => "Mills", 'age' => 20),
    array('id'=> "325E79", 'country' => 4, 'firstname' => "Dennis", 'surname' => "Ray", 'age' => 33),
    array('id'=> "32E478", 'country' => 4, 'firstname' => "Alex", 'surname' => "Fery", 'age' => 33),
    array('id'=> "3A4DB9", 'country' => 5, 'firstname' => "Rhoda", 'surname' => "Conner", 'age' => 35));

我還必須顯示該數組的所有內容，因為我必須顯示 ID、國家/地區、名字等。

我試圖按國家排序，然后選擇最年長的人，但我失敗了

function filtrar_por($data){
array_filter($data, function( $var ){
  for($i=0; $i <= 5; $i++){
    switch ($i) {
      case 0:
        $country0 = $var['country'] == $i;
        $country0 = ordenar_por($country0);
        echo $country0;
        break;
      case 1:
        $country1 = $var['country'] == $i;
        break;
      case 2:
        $country2 = $var['country'] == $i;
        break;
      case 3:
        $country3 = $var['country'] == $i;
        break;
      case 4:
        $country4 = $var['country'] == $i;
        break;
      case 5:
        $country5 = $var['country'] == $i;
        break;
    }        
  }
});
}

  function ordenar_por($data){
    foreach ($data as $clave => $fila) {
      $orden1[$clave] = $fila['age'];
    }
    array_multisort($orden1, SORT_DESC, $data);
    return $data;
  }

我試着用這個看看是否有效，但沒有。

Answer 1

像下面這樣使用usort：

<?php

$arrayPersonas = array(
    array('id'=> "0AB239", 'country' => 1, 'firstname' => "Ernest"  , 'surname' => "Austin", 'age' => 30),
    array('id'=> "12A179", 'country' => 0, 'firstname' => "Frances", 'surname' => "Poole", 'age' => 23),
    array('id'=> "1A90B9", 'country' => 1, 'firstname' => "Jacob", 'surname' => "Matthews", 'age' => 30),
    array('id'=> "227FF9", 'country' => 2, 'firstname' => "Mina", 'surname' => "Day", 'age' => 30),
    array('id'=> "2A6F39", 'country' => 3, 'firstname' => "Earl", 'surname' => "Mills", 'age' => 40),
    array('id'=> "325E79", 'country' => 4, 'firstname' => "Dennis", 'surname' => "Ray", 'age' => 33),
    array('id'=> "32E478", 'country' => 4, 'firstname' => "Alex", 'surname' => "Fery", 'age' => 50),
    array('id'=> "3A4DB9", 'country' => 5, 'firstname' => "Rhoda", 'surname' => "Conner", 'age' => 35));
    
$final_data = array();
function sortByOrder($a, $b) {
    return $a['age'] + $b['age'];
}

foreach( $arrayPersonas as $person){
    if(!empty($final_data[$person['country']])){
        foreach( $final_data[$person['country']] as $key => $value ){
            if( $final_data[$person['country']][$key]['age'] < $person['age'] ){
                unset($final_data[$person['country']][$key]);
                $final_data[$person['country']][] = $person;
            }else if( $final_data[$person['country']][$key]['age'] == $person['age'] ){
                $final_data[$person['country']][] = $person;
            }
        }
    }else{
        $final_data[$person['country']][] = $person;
        usort($final_data[$person['country']], 'sortByOrder');
    }
}
print_r($final_data);

代碼片段沙箱： http : //sandbox.onlinephpfunctions.com/code/8ffed1ebb2940fc71cd35cb8bfddae2e8ca3077c

Answer 2

我有另一種方法來找到你想要的結果。 它可能比 Burhan anwser 效率低一點，但我認為它更具可讀性。

<?php

$persons = array(
    array('id'=> "0AB239", 'country' => 1, 'firstname' => "Ernest"  , 'surname' => "Austin", 'age' => 30),
    array('id'=> "12A179", 'country' => 0, 'firstname' => "Frances", 'surname' => "Poole", 'age' => 23),
    array('id'=> "1A90B9", 'country' => 1, 'firstname' => "Jacob", 'surname' => "Matthews", 'age' => 30),
    array('id'=> "227FF9", 'country' => 2, 'firstname' => "Mina", 'surname' => "Day", 'age' => 30),
    array('id'=> "2A6F39", 'country' => 3, 'firstname' => "Earl", 'surname' => "Mills", 'age' => 20),
    array('id'=> "325E79", 'country' => 4, 'firstname' => "Dennis", 'surname' => "Ray", 'age' => 33),
    array('id'=> "32E478", 'country' => 4, 'firstname' => "Alex", 'surname' => "Fery", 'age' => 50),
    array('id'=> "3A4DB9", 'country' => 5, 'firstname' => "Rhoda", 'surname' => "Conner", 'age' => 35)
);
    
    // Get the different countries you can have
    $differentCountries = array_unique(array_column($persons, "country"));
    
    $result = [];
    
    
    // Loop over the different contries
    foreach ($differentCountries as $countryId) {
        
        // Get the all values for this specific country
        $valuesForThisCountry = array_filter($persons, function ($person) use ($countryId) {
            return $person["country"] == $countryId;
        });
        
        // Get an associative array with "id" as key and "age" as value
        $formattedArray = array_column($valuesForThisCountry, "age", "id");

        // Get the older ones
        $olders = array_keys($formattedArray, max($formattedArray));
        
        // Get the initial values of persons you found
        $personsById = array_filter($persons, function ($person) use ($olders) {
            // Check if the "id" is in the $olders
            return in_array($person["id"], $olders);
        });
        
        // Finally, put the result in the $result array
        $result = array_merge($result, $personsById);
        
    }
    
    
    print_r($result);

http://sandbox.onlinephpfunctions.com/code/464bf5fa58f75bdecbf85f49edfecefd3df90673

編輯：作為 anwsered Burhan Kashour，我編輯了代碼（只是編輯了最后一個合並行）

這是新版本http://sandbox.onlinephpfunctions.com/code/cb757dc7ae4862f6ac671f0cb36e057f18a8ced6