PHP check if certain value in different arrays are the same for all-CodePudding

I have couple of arrays like this

$arrayOne = array (
    "name" => 'john',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);

$arrayTwo = array (
    "name" => 'smith',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);  

$arrayThree = array (
    "name" => 'dave',
    "position" => 'instructor',
    "hired"  => '2009',
    "department" => 'math',
);

how can I check if these arrays all have the same hired date?

one way would be compare each individual one:

if($arrayOne['hired'] === $arrayTwo['hired']) & if($arrayOne['hired'] === $arrayThree['hired']) & ...

but is there a cleaner way to do this?

CodePudding user response：

Your initial question and subsequent comment are similar but they are attempting to do different things with the data, with different outcomes. The initial as-asked was:

how can I check if these arrays all have the same hired date

And that can be done with the following:

var_dump(count(array_unique(array_column([$arrayOne, $arrayTwo, $arrayThree], 'hired'))));

// or

$combined = [$arrayOne, $arrayTwo, $arrayThree];
$hiredValues = array_column($combined, 'hired');
$hiredValuesUnique = array_unique($hiredValues);
$length = count($hiredValuesUnique);
var_dump($length);

If the count is 1, they are the same, otherwise they aren't.

But, your follow-up comment was

how can I know which ones are the same

To do that, I'd create a new array that is keyed by that value, and foreach over the source arrays, effectively grouping similar ones for you to further act up.

$final = [];

foreach([$arrayOne, $arrayTwo, $arrayThree] as $array){
    if(!array_key_exists($array['hired'], $final)){
        $final[$array['hired']] = [];
    }
    $final[$array['hired']][] = $array;
}

var_dump($final);

Which produces:

array(2) {
  [2010]=>
  array(2) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "john"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
    [1]=>
    array(4) {
      ["name"]=>
      string(5) "smith"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
  }
  [2009]=>
  array(1) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "dave"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2009"
      ["department"]=>
      string(4) "math"
    }
  }
}

CodePudding user response：

I have written the code below:

//Your data
$arrayOne = array (
    "name" => 'john',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);

$arrayTwo = array (
    "name" => 'smith',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);  

$arrayThree = array (
    "name" => 'dave',
    "position" => 'instructor',
    "hired"  => '2009',
    "department" => 'math',
);  

function hiredIsTheSameEverywhere(...$arrays) : bool  
{
    return count(array_count_values(array_column($arrays, "hired"))) === 1; 
}

function whereHiredIsTheSame(...$arrays) : array 
{
    $return = [];
    $count = array_count_values(array_column($arrays, "hired"));
    foreach($arrays as $array) {
        if($count[$array['hired']] > 1) {
            $return[$array['hired']][] = $array;
        }
    }
    return $return;
}

//The output 
var_dump(hiredIsTheSameEverywhere($arrayOne, $arrayTwo, $arrayThree));
var_dump(whereHiredIsTheSame($arrayOne, $arrayTwo, $arrayThree));

output:

bool(false)
array(1) {
  [2010]=>
  array(2) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "john"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
    [1]=>
    array(4) {
      ["name"]=>
      string(5) "smith"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
  }
}