数组翻转并合并多个数组

Question

How do I go about making the following array:

Array
(
    [0] => Array
        (
            [r_id] => 1
            [r_rate] => 180.00
        )

    [1] => Array
        (
            [r_id] => 2
            [r_rate] => 100.00
        )

    [2] => Array
        (
            [r_id] => 3
            [r_rate] => 100.00
        )

    [3] => Array
        (
            [r_id] => 4
            [r_rate] => 100.00
        )

)

Look like this: (array value r_id = array key, with a value of r_rate)

Array
(
    [1] => 180.00 // [r_id] => [r_rate]
    [2] => 100.00
    [3] => 100.00
    [4] => 100.00

)

I have tried using array_flip and array_merge and looping through the array, but with very little success. The array name is $r_id.

Answer 1

You could just use a simple foreach for this purpose:

foreach($original_array as $values) {
    $new_array[$values['r_id']] = $values['r_rate'];
         //   ^ so the r_id assign it as key  ^ and the rate becomes the values
}

So finally you just get a flat array.