How to show total no. of age group

Question

i have a age data: 18,25,36,20,23,21,31,

Using php how i can show like this data? 10 to 20 years = 1 people, 20 to 30 years = 4 people, 30 to 40 years = 2 people

Answer 1

You could try something like this. It uses array_map to divide all values in the data by 10 (thus putting them in groups), then array_count_values to count the number of people in each group.

$ages = [18,25,36,20,23,21,31];
$groups = array_count_values(array_map(function ($v) { return (int)($v / 10); }, $ages));
for ($i = 0; $i <= max(array_keys($groups)); $i++) {
    echo $i*10 . " to " . ($i*10+9) . " years: " . (isset($groups[$i]) ? $groups[$i]: 0) . "\n";
}

Output:

0 to 9 years: 0 
10 to 19 years: 1 
20 to 29 years: 4 
30 to 39 years: 2

Update

If you don't want to display groups that have no people in them, use this loop instead:

for ($i = 0; $i <= max(array_keys($groups)); $i++) {
    if (isset($groups[$i])) echo $i*10 . " to " . ($i*10+9) . " years: " . $groups[$i] . "\n";
}

Output:

10 to 19 years: 1 
20 to 29 years: 4 
30 to 39 years: 2

Demo on 3v4l.org

Answer 2

There are many ways but I will prefer directly from mysql query, Something like this

SELECT IF (`age` < 10, '0 to 10 years',
          IF(`age` > 10 AND `age` < 20, '10 to 20 years', 
            IF(`age` > 20 AND `age` < 30, '20 to 30 years', 'more than 30 years')
          )
        ) AS age_group,
        count(*) as `counts`
  FROM `table_name`
  Group by `age_group`

You can refer this answer to calculate age from DOB stored in database

Answer 3

This code collected the birthday dates from your database and groups them for you in your desired ranges.

//Please update this section to grant access to your database
$username = 'root'; //Your Database Username
$password = ''; //Your Database Password
$database = 'test_sample'; //Your Database Name
$table_name = 'ages'; //Your Table Name
$column_name = 'date_of_birth'; // The Column where the birthday dates can be accessed

$query = 'SELECT `'.$column_name.'` FROM `'.$table_name.'`';
$db_connection = mysqli_connect('localhost', $username, $password, $database);

$result = mysqli_query($db_connection, $query);

$current_ages = [];
$now = new DateTime();
while($data = mysqli_fetch_array($result)) {
    $date = new DateTime($data[$column_name]);
    $interval = $now->diff($date);
    $current_ages[] = $interval->y;
}

// $current_ages = [18,25,36,20,23,21,31];

$desired_range = [
   [10,20], [21,30], [31,40], [41,50]
];

$result = [];
foreach($current_ages as $data) {
  foreach($desired_range as $index => $range) {
    if($data >= $range[0] && $data <= $range[1]) {
       (isset($result[$index]))? $result[$index]++ : $result[$index] = 1;
       break;
    }
  }
}

foreach($desired_range as $index => $range) {
    $count = (isset($result[$index]))? $result[$index] : 0;
    echo $range[0]." to ".$range[1]." years = ".$count.' <br/>';
}

Answer 4

$ages = [18,25,36,20,23,21,31];
$years = array(); // floor range
foreach ($ages as $age)
{
    $m = (int)($age / 10);
    (isset($years[($m*10)])) ? $years[($m*10)]++ : $years[($m*10)] = 1;
}
var_dump($years); // output: array(3) { [10]=> int(1) [20]=> int(4) [30]=> int(2) }