Filter rows of a 3d array where keys in a specific column satisfy a flat whitelist array

✔ Recommended Answer

• Prepare your whitelist so that the required values are the keys of a flat array.
• Call array_filter() to iterate each row of the sample array.
• Try to eliminate as many elements from the whitelist array using the row's discipline keys. If there are none remaining, then the row satisfies the whitelist and should be retained.

Code: (Demo)

$get['disciplines'] = ['second' => 2, 'third' => 4, 'fourth' => 12];$filterBy = array_flip($get['disciplines']);var_export(    array_filter(        $array,        fn($row) => !array_diff_key($filterBy, $row['disciplines'])    ));

Source: stackoverflow.com

Answered By: mickmackusa

Method #2

To filter rows of a 3D array where keys in a specific column satisfy a flat whitelist array, you can use the filter method along with the includes method. Here's an example code snippet that demonstrates this approach:

javascript
const arr3D = [
  [[1, 2, 3], 'foo'],
  [[4, 5, 6], 'bar'],
  [[7, 8, 9], 'baz'],
  [[10, 11, 12], 'qux'],
];

const whitelist = [2, 5, 8, 11];

const filteredArr3D = arr3D.filter((row) => {
  const key = row[0][1]; // assuming column 1 is the target column
  return whitelist.includes(key);
});

console.log(filteredArr3D);
// Output: [ [ [ 1, 2, 3 ], 'foo' ], [ [ 4, 5, 6 ], 'bar' ], [ [ 7, 8, 9 ], 'baz' ], [ [ 10, 11, 12 ], 'qux' ] ]

In this example, we have a 3D array arr3D with two columns. We want to filter the rows where the key in the second column is in the whitelist array. We use the filter method to iterate over the rows of the 3D array, and the includes method to check if the key is in the whitelist array. Finally, we return the rows that satisfy this condition.

Note that in this example, we assumed that column 1 is the target column. You can change the index value to target a different column.