Description: Sort Lists

This article explains how the online converter "Sort Lists" works. With this tool you can sort lists according to different criteria easily.

Different sorting methods

A list can be sorted with different methods. This online tool supports alphabetic sorting according to DIN 5007-1, phonebook sorting according to DIN 5007-2, natural sorting, as well as the reverse sort order. It is possible to arrange the sorted list in ascending order or in descending order and you can also determine if the sorting should be case sensitive or not.

Alphabetical Sorting (DIN 5007-1)

It should be clear, how to sort a list alphabetically. Only for a few characters, such as the german umlauts Ä, Ö and Ü, it is not immediately obvious how these should be classified. According to DIN 5007-1, this is done as follows:

• ä/Ä and a/A are equal
• ö/Ö and o/O are equal
• ü/Ü and u/U are equal
• ß and ss are equal

You can program this in PHP the following way:

$sorted_list = array();
$search = array("#Ä#u", "#ä#u", "#Ö#u", "#ö#u", "#Ü#u", "#ü#u", "#ß#u", "#-#u");
$replace = array("A", "a", "O", "o", "U", "u", "ss", " ");

$arr_replaced = preg_replace($search, $replace, $all_entries); // Replace characters

// If it shall be sorted case sensitive
if ($case_sensitive)
{
   asort($arr_replaced, SORT_STRING); // Sort alphabetically
}
// If it shall not be sorted case sensitive
else
{
   asort($arr_replaced, SORT_STRING | SORT_FLAG_CASE); // Sort alphabetically
}

foreach ($arr_replaced as $key => $value) $sorted_list[] = $all_entries[$key];

In principle, an additional array is created, in which the umlauts etc. are replaced. Afterwards this is sorted and then the original array is arranged in the same order.

Phonebook Sorting (DIN 5007-2)

In the so-called phonebook sorting according to DIN 5007-2, the umlauts are replaced in another way:

• ä/Ä and ae/Ae are equal
• ö/Ö and oe/Oe are equal
• ü/Ü and ue/Ue are equal
• ß and ss are equal

Furthermore, not the normal alphabetical sorting but the natural sorting is applied. In natural sorting, entries with numerical values are sorted in the same way a human would do. For a better understanding, have a look at this example:

This is the code for the phonebook sorting:

$sorted_list = array();
$search = array("#Ä#u", "#ä#u", "#Ö#u", "#ö#u", "#Ü#u", "#ü#u", "#ß#u", "#-#u");
$replace = array("Ae", "ae", "Oe", "oe", "Ue", "ue", "ss", " ");

$arr_replaced = preg_replace($search, $replace, $all_entries); // Replace characters

// If it shall be sorted case sensitive
if ($case_sensitive)
{
   natsort($arr_replaced); // Replace characters
}
// If it shall not be sorted case sensitive
else
{
   natcasesort($arr_replaced); // Replace characters
}

foreach ($arr_replaced as $key => $value)
{
   $sorted_list[] = $all_entries[$key];
}

Natural Sorting

The natural sorting was already explained in the previous section. The difference between this sorting method and the phonebook sorting is, that the umlauts etc. are replaced in the same way as in the alphabetical sorting:

$sorted_list = array();
$search = array("#Ä#u", "#ä#u", "#Ö#u", "#ö#u", "#Ü#u", "#ü#u", "#ß#u", "#-#u");
$replace = array("A", "a", "O", "o", "U", "u", "ss", " ");

$arr_replaced = preg_replace($search, $replace, $all_entries); // Replace characters

// If it shall be sorted case sensitive
if ($case_sensitive)
{
   natsort($arr_replaced); // Replace characters
}
// If it shall not be sorted case sensitive
else
{
   natcasesort($arr_replaced); // Replace characters
}

foreach ($arr_replaced as $key => $value)
{
   $sorted_list[] = $all_entries[$key];
}

Reverse Sorting

For the reverse sorting, we just have to reverse the array with the entries:

$sorted_list = array_reverse($all_entries);

The same function is also used when selecting a sorting method in decending order.

• share

Share this page

• share
• share

Related solvers

Description: Random Generator - YES / NO

In this article the algorithm of the "YES / NO" generator is described. The random generator randomly generates the answer Yes or No. If you are unsure and need an oracle, then this site will help you. With the cryptographically safe random generator you do not have to make any decisions by yourself.

Description: Text Converter - ROT Encryption

With ROT encryption, texts can be made unreadable at first glance. How this works and what the Online Converter from this platform all can do, you will find out here.

Description: Text Converter - Jumble Letters

This article describes how the text converter "Jumble Letters" works. In this converter, you can enter a text which is then converted into a text with jumbled letters.

Description: Text Converter - Lower- / Uppercase Letters

This article describes how the text converter "Lower- / Uppercase Letters" works. With this converter, you can transform a text completely into lowercase or uppercase letters.