PHP多重循环生成新数组

Question

我有一些数组，如下所示

 array(
    [0] =>
        array( ['direction'] =>  '0.000,0.160,0.123,0.104,0.000' )
    [1] =>
        array( ['direction'] =>  '0.000,0.101,0.237,0.101,0.000' )
    [2] =>
        array( ['direction'] =>  '0.000,0.160,0.125,0.163,0.000' )
  )

使用 for 循环，我想生成新的数组，看起来像

data1 = [0.000, 0.000, 0.000]
data2 = [0.160, 0.101, 0.160]
data3 = [0.123, 0.237, 0.125]
data4 = [0.104, 0.101, 0.163]
data5 = [0.000, 0.000, 0.000]

这意味着使用 for 循环，我想获取每一列的值，然后将该值分配给每个新数组。

我想做的是

$cnt = count($array);
$buildCnt = count($array['direction']);
for($i = 0; $i < $cnt; $i++){
    for($j = 0; $j < buildCnt; $j++){
     'i need to do something here
    }
}

有人帮帮我吗？？谢谢

Answer 1

我不知道是否有更好的方法通过数组函数，你也可以使用普通的 foreach 循环。像这样:

$original_array = array(
    array('direction' => '0.000,0.160,0.123,0.104,0.000'),
    array('direction' => '0.000,0.101,0.237,0.101,0.000'),
    array('direction' => '0.000,0.160,0.125,0.163,0.000'),
);
$new_array = array();
foreach($original_array as $sub_array) {
    // loop each sub array
    $pieces = explode(',', $sub_array['direction']);
    // explode by comma
    foreach($pieces as $key => $piece) {
        // each piece, push by data(n)
        $new_array["data".($key+1)][] = $piece;
        // if you don't want to use extract
        // ${"data".($key+1)}[] = $piece;
    }
}

extract($new_array); // import newly created sub arrays
echo '<pre>';
print_r($data1); // $data2, $data3, ... and so on

$data1 应该是这样的:

Array
(
    [0] => 0.000
    [1] => 0.000
    [2] => 0.000
)