Generate multi dimensional PHP array using range - php

Question

The job to be done is show the price of postage per KG. So starting at 1KG, I want to increase by 0.50 for every KG.
I tried doing it like this which doesn't seem to work for me:
$shipping_second_class = array (
array ('weight' => range(1,5), 'cost' => range(1,3, 0.50))
);
foreach ($shipping_second_class as $shipping_second_class) {
echo('weight '.$shipping_second_class['weight'].' costs £'.$shipping_second_class['cost'].'<br/>');
}
That doesn't seem to work. What I'm trying to do in a way that's easier to maintain is something like this, but with less code:
$shipping_second_class = array (
array ('weight' => '1', 'cost' => '1'),
array ('weight' => '2', 'cost' => '1.5'),
array ('weight' => '3', 'cost' => '2'),
array ('weight' => '4', 'cost' => '2.5'),
array ('weight' => '5', 'cost' => '3'),
);
foreach ($shipping_second_class as $shipping_second_class) {
echo('weight '.$shipping_second_class['weight'].' costs £'.$shipping_second_class['cost'].'<br/>');
}

Answer 1

Another simple way
$per_kg_extra_cost = 0.5;
foreach (range(0, 4) as $shipping) {
$cost = 1 + ( $shipping * $per_kg_extra_cost );
$weight = ++$shipping;
echo '<pre>';
echo 'Weight: '. $weight . ' cost : ' .$cost;
}

Answer 2

Here's one way to do this:
$shipping_second_class = array (
array ('weight' => 1, 'cost' => 1)
);
for($x = 2; $x < 6; $x++){
$newdata = ['weight' => $x, 'cost' => 0.5 + $x * 0.5];
array_push($shipping_second_class, $newdata);
}
foreach ($shipping_second_class as $s) {
echo('weight '.$s['weight'].' costs £'.$s['cost'].'<br/>');
}
Essentially, you need to add to the array after it's been called rather than initialize it fully filled. You start with the array at 1 value (you could modify this code to start with an empty array) and it expands from there. If you need to add more to the array, just increase the 6 to (Desired Number) + 1 in the for loop.
I'm not sure if there is a way to add to the array in the manner you do in the first block of code.

Answer 3

Here is a simple way to do it:
$key = -1;
$interval = 0.5;
$shipping_second_class = array_map(function($v) use (&$key,$interval) {
$key++;
return ["weight"=>$v,"cost"=>(1 + ($interval * $key))];
},range(1,5));
echo json_encode($shipping_second_class);
You can change the $interval variable if you need to change the way it increments cost