重组PHP数组结构（数组中的数组）

Question

I have this array within array which contains a lot of values:

  183 => 
    array (size=3)
      0 => string 'DE' (length=2)
      1 => string '2015-06-09' (length=10)
      2 => string 'GK' (length=2)   
  184 => 
    array (size=3)
      0 => string 'DE' (length=2)
      1 => string '2015-06-08' (length=10)
      2 => string 'GL' (length=2)   
  185 => 
    array (size=3)
      0 => string 'FR' (length=2)
      1 => string '2015-06-09' (length=10)
      2 => string 'GN' (length=2)   
  186 => 
    array (size=3)
      0 => string 'FR' (length=2)
      1 => string '2015-09-08' (length=10)
      2 => string 'GO' (length=2)

0 is the country code. 1 is a date. 2 is a column on an Excel file.

I want to organize it in this way:

2015-06-09 => 
  array (size=3)
    DE => 
      array (size=2)
        column => GK
        download => 666 
    FR => 
      array (size=2)
        column => GN
        download => 777 

2015-06-08 =>
  array (size=3)
    DE => 
      array (size=2)
        column => GL
        download => 666 
    FR => 
      array (size=2)
        column => GO
        download => 777 

So the same date can show up more than once. if it gets to an array value with the same date - it inserts in it the country code with and its' column.

if it has more than 1 country - it adds a new country. (with the 'download' and column values).

I have this function:

function get_cols_to_array_by_date($array) { 

    $mainarr = array();

    $last_in_arr = count($array); 

    for ($i=0; $i<$last_in_arr; $i++){

            $mainarr[$array[$i][1]] = array( $array[$i][0]=> array('downloads'=> 666, 'col'=>$array[$i][2]) );


    }

    return $mainarr;


}

which outputs an array that runs over the country when it gets to the same date and doesn't give me an array of countries.

What part am I missing in my code? Is there a simpler way to do it? ( PHP syntax shortcuts ;) )

Answer 1

Assuming that the downloads is the key of the initial array, and each element has 3 elements(date and 2 countries):

Code:

//demo array
    $old = array(
        555=>array(
          0 => 'DE',
          1 => '2015-06-09',
          2 => 'GK'), 
        234=>array(
          0 => 'DE',
          1 => '2015-06-08',
          2 => 'GL'),   
        123=>array(
          0 => 'FR', 
          1 => '2015-06-09',
          2 => 'GN')
          );  

    $new = array();   
    foreach($old as $key=>$arrayValues)
    {
        if(!array_key_exists($arrayValues[1], $new)){ //check if there is already a key by date
            $new[$arrayValues[1]] = array();
        }
        $new[$arrayValues[1]][$arrayValues[0]] = array('column'=>$arrayValues[2], 'downloads'=>$key); //append formated array
    }
    echo "<pre>";
    var_dump($new);
    echo "</pre>";

Output:

array(2) {
  ["2015-06-09"]=>
  array(2) {
    ["DE"]=>
    array(2) {
      ["column"]=>
      string(2) "GK"
      ["downloads"]=>
      int(555)
    }
    ["FR"]=>
    array(2) {
      ["column"]=>
      string(2) "GN"
      ["downloads"]=>
      int(123)
    }
  }
  ["2015-06-08"]=>
  array(1) {
    ["DE"]=>
    array(2) {
      ["column"]=>
      string(2) "GL"
      ["downloads"]=>
      int(234)
    }
  }
}

Answer 2

Try looping and checking if element exists, if not - add it.

$result = [];

foreach ($myArray as $key => $values) {
    if (!isset($result[$values[1]])) {
        $result[$values[1]] = [
            $values[0] => [
                'column' => $values[2],
                'download' => $key,
            ]
        ];
    } elseif (!isset($result[$values[1]][$values[0]])) {
        $result[$values[1]][$values[0]] = [
            'column' => $values[2],
            'download' => $key,
        ];
    }
}

Sandbox