How to fill an array with a property of another?

Question

PHP

Task. Fill array $b with numbers 1, 2, 3, 4 only.

$a = [
  [1, 1000],
  [2, 1500],
  [3, 2000],
  [4, 2500],
];

$b = [];
foreach($a as $v){
  $b[] = $v[0];
}

Is there a function, in one line, that can do this? No cycle like mine.

Answer 1

array_column