How can I sort this array

array:3 [▼
  0 => array:2 [▼
    "examCourseId" => "1039"
    "total" => 2.3
  ]
  1 => array:2 [▼
    "examCourseId" => "1039"
    "total" => -3.0
  ]
  2 => array:2 [▼
    "examCourseId" => "10007"
    "total" => 15.5
  ]
]

For examCourseId = 1039 it need to be

[2.3, -3.0]

For examCourseId = 10007 it need to be

[15.5]


Total Array should be

[
  [2.3, -3.0],
  [15.5]
]

$group = array();
 foreach (array as $value) {
   $group[$value['examCourseId']][] = $value;
}