What is a symmetric list creator?
This online utility creates symmetrical lists. A symmetrical list is also known as a palindromic list. Such lists can be read from the beginning to end and from the end to beginning and in both directions they will have the same items. For example, a list "x, y, z, y, x" is a palindromic list because it has the same items from the beginning and end. Here's a more detailed example. If you have another list "a, b, b", then this program makes it symmetrical by adding as many items as required to form symmetry. There are several symmetry types possible for this list. The first one is called mirror symmetry and it duplicates absolutely all the items of the given list in reverse order. In this case, the mirror-symmetric list would be "a, b, b, b, b, a" (the underlined items are the added items, which are the reversed original list). The second type is called centered symmetry. In this case, all the items except the last one are duplicated and the last one is the only item without a matching pair. In this symmetry mode, the list looks like this "a, b, b, b, a" (the underlined items are the new added items that form a symmetric list). The third type of symmetry is called minimal symmetry. When this type is used, the application creates symmetry by trying to add the minimum number of possible items to the list. Here, we get the following list: "a, b, b, a" (only one underlined item had to be added to form a symmetric list). You can create all these symmetry types from any list of any format. You just need to specify which item separator is used in the list. If it is a regular character (such as a comma, a space, or a semicolon), you can specify it in the options. If it is several different characters (such as space and a newline, or a comma and a semicolon), you can match them using a regular expression. Also, you can specify a new separating symbol for the symmetric list and ignore empty items when forming a symmetric list. Listabulous!
