Question

我有一组从数据库中提取的“答案”（多维数组）。我需要对每个值执行计算，以便我可以在图表上显示结果。

以下是一些示例输入：

$array = [
    'A1' => [1 => 1, 2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
    'A2' => [1 => 1, 2 => 1, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
    'A3' => [1 => 0, 2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0]
];

我想使用这种逻辑从多维数组计算一个百分比值：

[A1] => Array( ([1]*100/sum([1]+[1]+[1]), [2]*100/sum([2]+[2]+[2]),..... )
[A2] => Array( ([1]*100/sum([1]+[1]+[1]), [2]*100/sum([2]+[2]+[2]),..... )
[A3] => Array( ([3]*100/sum([1]+[1]+[1]), [2]*100/sum([2]+[2]+[2]),..... )

我该怎么做？

我想要的输出：

[
  'A1' => [1 => 50, 2 => 0,   3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
  'A2' => [1 => 50, 2 => 100, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
  'A3' => [1 => 0,  2 => 0,   3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0]
]

Answer 1

啊，我看到你现在要做的事。

试试这个

$totals = array();

// First get our totals.
foreach ($mainArray as $subKey => $subArray) {
    foreach ($subArray as $k => $v) {
        // Add the column to our total.
        $totals[$k] = isset($totals[$k]) ? $totals[$k] + $v : $v;
    }
}

$answers = array();
// Then build our answers.
foreach ($mainArray as $subKey => $subArray) {
    $answers[$subKey] = array();
    foreach ($subArray as $k => $v) {
        $answers[$subKey][$k] = ($v * 100) / $totals[$k];
    }
}

print_r($answers);

Answer 2

达斯汀的答案引起了很多除数为零的警告，所以我想我会花点时间写自己的答案。

由于示例输入数组具有相等长度的子数组，因此我不会理会isset()，而只是相信从第一行调用array_column()将访问所有可用值。

首先，声明foreach() $v，但未使用，因为array_column()与其他垂直数据一起收集。 $column_totals是一维求和的数组。

由于必须对多维输入数组的每个元素进行单独的计算，因此使用了两个循环。

在执行计算之前，请检查“当前值”和“列总和值” 为零值将启用0的快速返回（并避免出现警告）；否则，请使用OP的公式。

*对于不熟悉Order of Operations的人，公式中不需要括号，因为从左到右读取表达式将保持*和/的逻辑。 / p>

代码：（演示）

$array = [
    'A1' => [1 => 1, 2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
    'A2' => [1 => 1, 2 => 1, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0],
    'A3' => [1 => 0, 2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 0, 10 => 0]
];

foreach (current($array) as $k => $v) {
    $column_totals[$k] = array_sum(array_column($array, $k));
}

foreach ($array as $key => $row) {
    foreach ($row as $k => $v) {
        $result[$key][$k] = (!$v || !$column_totals[$k]) ? 0 : $v * 100 / $column_totals[$k];
    }
}
var_export($result);

输出：

array (
  'A1' => 
  array (
    1 => 50,
    2 => 0,
    3 => 0,
    4 => 0,
    5 => 0,
    6 => 0,
    7 => 0,
    8 => 0,
    9 => 0,
    10 => 0,
  ),
  'A2' => 
  array (
    1 => 50,
    2 => 100,
    3 => 0,
    4 => 0,
    5 => 0,
    6 => 0,
    7 => 0,
    8 => 0,
    9 => 0,
    10 => 0,
  ),
  'A3' => 
  array (
    1 => 0,
    2 => 0,
    3 => 0,
    4 => 0,
    5 => 0,
    6 => 0,
    7 => 0,
    8 => 0,
    9 => 0,
    10 => 0,
  ),
)

如何使用列数据的总和对多维数组的每个值进行数学运算？

2 个答案: