如何从小于值的数组中获取子数组键
How To get sub array keys from array by less than values
我想从数组中获取小于值的子数组键。
这是一个例子：
$arr_less_than = array(55,60,10,70);
$BlackList = array(10,8,15,20);
$MasterArray = array(
10 => array(1 => array(50,20,5,40), 2 => array(70,77,58,10), 3 => array(155,95,110,105), 4 => array(250,215,248,188)),
11 => array(1 => array(5,65,49,100), 2 => array(80,85,60,30), 3 => array(175,85,95,120), 4 => array(235,205,218,284)),
12 => array(1 => array(82,80,55,80), 2 => array(90,90,74,110), 3 => array(180,122,156,222), 4 => array(255,225,233,263)),
13 => array(1 => array(350,360,400,375), 2 => array(95,99,111,75), 3 => array(188,112,66,111), 4 => array(66,69,33,110)),
);
如果子数组键不在数组 $BlackList.
中，现在我需要从 $MasterArray 获取小于 $arr_less_than 的子数组键
对于上面的例子，结果必须return array(12,13).
注意：我不想使用 foreach 循环
这里有 2 种解决方案 - 一种适用于所有满足条件的子阵列，一种适用于任何满足条件的子阵列（这似乎是 OP 的想法）。最后，对于后一种情况，在任何子数组满足条件的情况下，都有基于 foreach 的解决方案。
如果我对问题的理解正确，目标是识别 MasterArray 中所有子数组的值都大于 $arr_less_than.
中对应值的行
OP 不想使用 foreach（请参阅答案的结尾以了解基于 foreach 的答案，这些答案要简单得多）——这实际上可能会产生更多高效版本，因为它可以避免不必要的比较并节省一些周期，所以这里是一个使用数组函数的大量注释版本。
我排除了可以从 OP 复制的数据 post:
function getMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray), // Iterate over $MasterArray's keys (Because we need the keys for the BlackList)
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
// Filter out MasterArray Entries that dont meet the criteria
echo "Evaluate $MasterArray[$v]" . PHP_EOL;
// Remove array entries whose key is in the BlackList
if (in_array($v, $BlackList)) {
echo "\tBlacklisted" . PHP_EOL;
return false;
}
// For each entry in the MasterArray value, add up the number of non-matching entries
$y = array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
// For each subarray entry in a MasterArray value, reduce the array to a count
// of elements whose value is less than the corresponding value in the $arr_less_than
$s1 = array_reduce(
array_keys($sub),
function ($carry, $key) use ($sub, $arr_less_than) {
if ($sub[$key] <= $arr_less_than[$key]) {
return ++$carry;
}
},
0 // Initial value for the array_reduce method
);
// $s1 will be a count of non-matching values
return $c1 + $s1;
},
0 //Initial value for the array_reduce method
);
echo "\t$y" . PHP_EOL;
// Include the array value in the filter only if there are no non-matching values ($y == 0)
return !$y;
}
)
);
}
print_r(getMatchingRows($arr_less_than, $MasterArray, $BlackList));
基本思想是从最外层数组生成键列表 - 因此我们使用 array_filter 迭代它们。然后我们排除那些在黑名单中有密钥的人。不在黑名单中的行通过遍历每个 sub=arrays 值并将它们按位置与 $arr_less_than 进行比较并将每个不大于 $ 中相应成员的值加 1 来减少为整数arr_less_than。然后对 MasterArray 行中所有成员的这些值求和。如果结果为零，则该行通过。最后将最终结果传递给array_values对结果数组进行归一化处理
请注意，这需要比较所有值，即使第一个子数组中的第一个子值失败。因此，可以转义的 foreach 方法可能更有效。
这基本上是相同的方法，没有注释和几个快捷方式：
function getMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray),
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
return !in_array($v, $BlackList) && !array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
return $c1 ?: array_reduce(
array_keys($sub),
function ($carry, $key) use ($sub, $arr_less_than) {
return $carry ?: ($sub[$key] <= $arr_less_than[$key] ? 1 : 0);
},
0
);
},
0
);
}
)
);
}
array_reduce 中的某些方法使用 ?: 运算符进行了短路，因为实际计数是无关紧要的。一旦计数超过零，该行将失败，无论如何。
如果标准是至少一个子数组的所有成员都大于参考数组，那么这里是类似的代码。
function getMatchingRowsAny($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray), // Iterate over $MastrArray's keys (Because we need the keys for theBlackList)
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
// Filter out MasterArray Entries that dont meet the criteria
echo "Evaluate \MasterArray[$v]" . PHP_EOL;
// Remove array entries whose key is in the BlackList
if (in_array($v, $BlackList)) {
echo "\tBlacklisted" . PHP_EOL;
return false;
}
// For each entry in the MasterArray value, add up the number of non-matching entries
$y = array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
// For each subarray entry in a MasterArray value, reduce the array to a flag
// indicating if it has whose value is <= the corresponding value in the $arr_less_than
$s1 = array_reduce(
array_keys($sub),
function ($fail, $key) use ($sub, $arr_less_than) {
return $fail || $sub[$key] <= $arr_less_than[$key];
},
false
);
// This could be short-circuited above to avoid an unnecessary array_reduce call
return $c1 || !$s1;
},
false
);
echo "\t$y" . PHP_EOL;
// Include the array value in the filter if there are any matching values
return $y;
}
)
);
}
print_r(getMatchingRowsAny($arr_less_than, $MasterArray, $BlackList));
作为一个练习（因为我是一个贪吃的惩罚）我使用 foreach 呈现相同的方法作为生成器和返回数组的函数 - 主要是为了说明 foreach 可能更好选择，绝对更简单：
// Implemented as a generator - The associated foreach that uses it follows
function generateMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
foreach ($MasterArray as $k => $v) {
if (in_array($k, $BlackList)) {
continue;
}
foreach ($v as $sub_array) {
$match = true;
foreach ($sub_array as $k1 => $v1) {
if ($v1 <= $arr_less_than[$k1]) {
$match = false;
break;
}
}
if ($match) {
yield $k;
break;
}
}
}
}
foreach (generateMatchingRows($arr_less_than, $MasterArray, $BlackList) as $k) {
echo $k . PHP_EOL; // Or push them onto an array
}
// Implemented as a function returning an array - classical approach - just return an array
function getMatchingRowsForEach($arr_less_than, $MasterArray, $BlackList)
{
$rv = [];
foreach ($MasterArray as $k => $v) {
if (in_array($k, $BlackList)) {
continue;
}
foreach ($v as $sub_array) {
$match = true;
foreach ($sub_array as $k1 => $v1) {
if ($v1 <= $arr_less_than[$k1]) {
$match = false;
break;
}
}
if ($match) {
$rv[] = $k;
break;
}
}
}
return $rv;
}
print_r(getMatchingRowsForEach($arr_less_than, $MasterArray, $BlackList));
我想从数组中获取小于值的子数组键。
这是一个例子：
$arr_less_than = array(55,60,10,70);
$BlackList = array(10,8,15,20);
$MasterArray = array(
10 => array(1 => array(50,20,5,40), 2 => array(70,77,58,10), 3 => array(155,95,110,105), 4 => array(250,215,248,188)),
11 => array(1 => array(5,65,49,100), 2 => array(80,85,60,30), 3 => array(175,85,95,120), 4 => array(235,205,218,284)),
12 => array(1 => array(82,80,55,80), 2 => array(90,90,74,110), 3 => array(180,122,156,222), 4 => array(255,225,233,263)),
13 => array(1 => array(350,360,400,375), 2 => array(95,99,111,75), 3 => array(188,112,66,111), 4 => array(66,69,33,110)),
);
如果子数组键不在数组 $BlackList.
$MasterArray 获取小于 $arr_less_than 的子数组键
对于上面的例子，结果必须return array(12,13).
注意：我不想使用 foreach 循环
这里有 2 种解决方案 - 一种适用于所有满足条件的子阵列，一种适用于任何满足条件的子阵列（这似乎是 OP 的想法）。最后，对于后一种情况，在任何子数组满足条件的情况下，都有基于 foreach 的解决方案。
如果我对问题的理解正确，目标是识别 MasterArray 中所有子数组的值都大于 $arr_less_than.
OP 不想使用 foreach（请参阅答案的结尾以了解基于 foreach 的答案，这些答案要简单得多）——这实际上可能会产生更多高效版本，因为它可以避免不必要的比较并节省一些周期，所以这里是一个使用数组函数的大量注释版本。
我排除了可以从 OP 复制的数据 post:
function getMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray), // Iterate over $MasterArray's keys (Because we need the keys for the BlackList)
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
// Filter out MasterArray Entries that dont meet the criteria
echo "Evaluate $MasterArray[$v]" . PHP_EOL;
// Remove array entries whose key is in the BlackList
if (in_array($v, $BlackList)) {
echo "\tBlacklisted" . PHP_EOL;
return false;
}
// For each entry in the MasterArray value, add up the number of non-matching entries
$y = array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
// For each subarray entry in a MasterArray value, reduce the array to a count
// of elements whose value is less than the corresponding value in the $arr_less_than
$s1 = array_reduce(
array_keys($sub),
function ($carry, $key) use ($sub, $arr_less_than) {
if ($sub[$key] <= $arr_less_than[$key]) {
return ++$carry;
}
},
0 // Initial value for the array_reduce method
);
// $s1 will be a count of non-matching values
return $c1 + $s1;
},
0 //Initial value for the array_reduce method
);
echo "\t$y" . PHP_EOL;
// Include the array value in the filter only if there are no non-matching values ($y == 0)
return !$y;
}
)
);
}
print_r(getMatchingRows($arr_less_than, $MasterArray, $BlackList));
基本思想是从最外层数组生成键列表 - 因此我们使用 array_filter 迭代它们。然后我们排除那些在黑名单中有密钥的人。不在黑名单中的行通过遍历每个 sub=arrays 值并将它们按位置与 $arr_less_than 进行比较并将每个不大于 $ 中相应成员的值加 1 来减少为整数arr_less_than。然后对 MasterArray 行中所有成员的这些值求和。如果结果为零，则该行通过。最后将最终结果传递给array_values对结果数组进行归一化处理
请注意，这需要比较所有值，即使第一个子数组中的第一个子值失败。因此，可以转义的 foreach 方法可能更有效。
这基本上是相同的方法，没有注释和几个快捷方式：
function getMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray),
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
return !in_array($v, $BlackList) && !array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
return $c1 ?: array_reduce(
array_keys($sub),
function ($carry, $key) use ($sub, $arr_less_than) {
return $carry ?: ($sub[$key] <= $arr_less_than[$key] ? 1 : 0);
},
0
);
},
0
);
}
)
);
}
array_reduce 中的某些方法使用 ?: 运算符进行了短路，因为实际计数是无关紧要的。一旦计数超过零，该行将失败，无论如何。
如果标准是至少一个子数组的所有成员都大于参考数组，那么这里是类似的代码。
function getMatchingRowsAny($arr_less_than, $MasterArray, $BlackList)
{
return array_values( // When we're done we just want a straight array of the keys from $MasterArray
array_filter(
array_keys($MasterArray), // Iterate over $MastrArray's keys (Because we need the keys for theBlackList)
function ($v) use ($BlackList, $MasterArray, $arr_less_than) {
// Filter out MasterArray Entries that dont meet the criteria
echo "Evaluate \MasterArray[$v]" . PHP_EOL;
// Remove array entries whose key is in the BlackList
if (in_array($v, $BlackList)) {
echo "\tBlacklisted" . PHP_EOL;
return false;
}
// For each entry in the MasterArray value, add up the number of non-matching entries
$y = array_reduce(
$MasterArray[$v],
function ($c1, $sub) use ($arr_less_than) {
// For each subarray entry in a MasterArray value, reduce the array to a flag
// indicating if it has whose value is <= the corresponding value in the $arr_less_than
$s1 = array_reduce(
array_keys($sub),
function ($fail, $key) use ($sub, $arr_less_than) {
return $fail || $sub[$key] <= $arr_less_than[$key];
},
false
);
// This could be short-circuited above to avoid an unnecessary array_reduce call
return $c1 || !$s1;
},
false
);
echo "\t$y" . PHP_EOL;
// Include the array value in the filter if there are any matching values
return $y;
}
)
);
}
print_r(getMatchingRowsAny($arr_less_than, $MasterArray, $BlackList));
作为一个练习（因为我是一个贪吃的惩罚）我使用 foreach 呈现相同的方法作为生成器和返回数组的函数 - 主要是为了说明 foreach 可能更好选择，绝对更简单：
// Implemented as a generator - The associated foreach that uses it follows
function generateMatchingRows($arr_less_than, $MasterArray, $BlackList)
{
foreach ($MasterArray as $k => $v) {
if (in_array($k, $BlackList)) {
continue;
}
foreach ($v as $sub_array) {
$match = true;
foreach ($sub_array as $k1 => $v1) {
if ($v1 <= $arr_less_than[$k1]) {
$match = false;
break;
}
}
if ($match) {
yield $k;
break;
}
}
}
}
foreach (generateMatchingRows($arr_less_than, $MasterArray, $BlackList) as $k) {
echo $k . PHP_EOL; // Or push them onto an array
}
// Implemented as a function returning an array - classical approach - just return an array
function getMatchingRowsForEach($arr_less_than, $MasterArray, $BlackList)
{
$rv = [];
foreach ($MasterArray as $k => $v) {
if (in_array($k, $BlackList)) {
continue;
}
foreach ($v as $sub_array) {
$match = true;
foreach ($sub_array as $k1 => $v1) {
if ($v1 <= $arr_less_than[$k1]) {
$match = false;
break;
}
}
if ($match) {
$rv[] = $k;
break;
}
}
}
return $rv;
}
print_r(getMatchingRowsForEach($arr_less_than, $MasterArray, $BlackList));