извлечение и групповые данные из многомерного массива

Question

Я хочу распечатать информацию из многомерного массива.

Вот моя структура массива:

// A two-dimensional array 
$cars=array 
(
    array('service' => "Windows8",'host' => Sydney1,'state' => on), 
    array('service' => "unix",'host' => Newyork2,'state' => off), 
    array('service' => "Windows8",'host' => Singapore3,'state' => on), 
    array('service' => "unix",'host' => Tokyo4,'state' => off), 
    array('service' => "Windows8",'host' => Tokyo4,'state' => on), 
); 

Я хочу организовать данные для распечатки следующего:

данных, сгруппированных по службе: желаемый результат:

Windows8 (3): Sydney1 (on), Singapore3 (on), Tokyo4 (on) 
unix (2): Newyork2 (off), Tokyo4 (off) 

данных сгруппированных по хост-функции: желаемый результат:

Sydney1 (1): Windows8 (on) 
Newyork2 (1): unix (off) 
Singapore3 (1): Windows8 (on) 
Tokyo4 (2): unix (off), Windows8 (on) 

Вот код, который я пытался до сих пор:

$arr = array(); 

    foreach($cars as $key => $item) 
    { 
     $arr[$item['service_name']][$key] = $item; 
    } 
    echo '<pre>';  
    print_r($arr); 
    echo '</pre>'; 

    $size = sizeof($arr); 
    $i=1; 
    foreach($arr as $key => $item) 
    { 
     echo $key; 
    } 

Answer 1

Хитрость манипулирование массивами состоит в том, чтобы организовать их в структуры данных, которые облегчат вам получение необходимых данных.

$cars=array (
     array('service' => "Windows8",'host' => 'Sydney1','state' => 'on'), 
     array('service' => "unix",'host' => 'Newyork2','state' => 'off'), 
     array('service' => "Windows8",'host' => 'Singapore3','state' => 'on'), 
     array('service' => "unix",'host' => 'Tokyo4','state' => 'off'), 
     array('service' => "Windows8",'host' => 'Tokyo4','state' => 'on'), 
); 

# initialise an array to group data by service and by location 
$data = array(); 

foreach ($cars as $c) { 
    # the key is the service name, and the value is an array of host/state pairs 
    $data['by_service'][ $c['service'] ][] = array($c['host'] , $c['state']); 

    # the key is the location name, and the value is an array of service/state pairs 
    $data['by_location'][ $c['host'] ][] = array($c['service'] , $c['state']); 
} 

# create a function that we can use to print data from the pairs in the 
# data structures above: it creates a string with the first array item 
# followed by the second item in brackets 
function print_arr ($arr) { 
    return $arr[0] . " (" . $arr[1] . ")"; 
} 

# group by service: 
foreach ($data['by_service'] as $s => $host) { 
    # print the service type, $s, and count the number of hosts 
    echo "$s (" . count($host) . "): "; 

    # print the details for the individual hosts, using print_arr for the details 
    # array_map is an extremely useful function that allows you to apply a function 
    # to every member of an array. It saves having to create new arrays or alter 
    # the array using foreach and you can include it in an echo statement. 
    echo implode(", ", array_map("print_arr", $host)) . "\n"; 
} 

echo "\n\n"; 

# group by location 
foreach ($data['by_location'] as $l => $host) { 
    # print the location and the count for the number of hosts 
    echo "$l (" . count($host) . "): "; 
    echo implode(", ", array_map("print_arr", $host)) . "\n"; 
} 

Выход:

Windows8 (3): Sydney1 (on), Singapore3 (on), Tokyo4 (on) 
unix (2): Newyork2 (off), Tokyo4 (off) 


Sydney1 (1): Windows8 (on) 
Newyork2 (1): unix (off) 
Singapore3 (1): Windows8 (on) 
Tokyo4 (2): unix (off), Windows8 (on) 

Вы можете найти print_r из $data структуры полезно, если вы заблудиться в коде.

Answer 2

$cars=array 
    (
    array('service'=> "Windows8",'host'=> 'Sydney1','state' => 'on'), 
    array('service'=> "unix",'host' => 'Newyork2','state' => 'off'), 
    array('service'=> "Windows8",'host'=> 'Singapore3','state'=> 'on'), 
    array('service'=> "unix",'host' => 'Tokyo4','state' => 'off'), 
    array('service'=> "Windows8",'host'=> 'Tokyo4','state' => 'on'), 
    ); 


    $windows = array(); 
    $i   = 0; 
    $j   = 0; 
while(list($carval, $value) = each($cars)) 
{ 

    // echo $key." = ".$value."<br>\n"; 
    if($value['service']=="Windows8"){ 
     $windows[$i++] = $value['host']."(".$value['state'].")";    
    } 
    else{ 
     $unix[$j++] = $value['host']."(".$value['state'].")";   
    } 


} 
echo "Windows8 (".count($windows).") : "; 
foreach($windows as $vall) 
{ 
    echo $vall.", "; 
} 

echo "<br>Unix (".count($unix).") : "; 

foreach($unix as $vall) 
{ 
    echo $vall.", "; 
} 

это для первой части ждать плохого поймать вас с полным анс ...

Answer 3

<?php 

$cars = array 
(
    array('service' => 'Windows8','host' => 'Sydney1','state' => 'on'), 
    array('service' => 'unix','host' => 'Newyork2','state' => 'off'), 
    array('service' => 'Windows8','host' => 'Singapore3','state' => 'on'), 
    array('service' => 'unix','host' => 'Tokyo4','state' => 'off'), 
    array('service' => 'Windows8','host' => 'Tokyo4','state' => 'on'), 
); 

// Create the output array 
$output = array(); 
foreach($cars as $car) 
{ 
    // If the service isn't added yet, add it otherwise increase it 
    // I do it this way to prevent the php warning 
    if(empty($output[$car["service"]]["count"])) $output[$car["service"]]["count"] = 1; 
    else $output[$car["service"]]["count"]++; 

    // Add the host, only if its not exists on the specific service 
    if(!in_array($car["host"], $output[$car["service"]]["hosts"])) 
     $output[$car["service"]]["hosts"][] = $car["host"]; 

    // Check if the states there within the host as key 
    if(!array_key_exists($car["host"], $output[$car["service"]]["states"])) 
     $output[$car["service"]]["states"][$car["host"]] = $car["state"]; 
} 

// Create the first output 
foreach($output as $service => $data) 
{ 
    $hosts = array(); 
    foreach($data["hosts"] as $index => $host) 
     $hosts[] = $host . "(" . $data["states"][$host] . ")"; 

    // Combine the hosts to the string 
    $hosts = implode(", ", $hosts); 

    echo $service . "(" . $data["count"] . ") : " . $hosts; 
    echo "<br />"; // HTML new line ? 
} 

// Now the second output, prepare it 
$hosts = array(); // Let's store the hosts here, to make the code simple to read :) 
foreach($output as $service => $data) 
{ 
    foreach($data["hosts"] as $index => $host) 
     $hosts[$host][] = $service . "(" . $data["states"][$host] . ")"; 
} 

// Print it 
foreach($hosts as $hostName => $hostData) 
{ 
    $hostValue = array(); 

    foreach($hostData as $service) 
     $hostValue[] = $service; 

    echo $hostName . "(" . count($hostData) . ") \t\t: " . implode(", ", $hostValue); 
    echo "<br />"; // HTML new line ? 
}