Overline

The term overline denotes the Unicode character U 203 E (English overline ), and U 0305 ( combining overline, English for " Recombinant overline "). The graphical award one or more words with a solid line above the character is referred to as a sweep. Depending on the context in which is used the overline, he has a different meaning.

Colloquially the overline is also called " top line". This term is ambiguous and says traditionally the apostrophe.

Available characters

In multiple character sets of ISO 8859 family of standards and, derived also in the Unicode standard, a character U 00 AF ( 175dec ), which can be used as equally over-bar as well as a macron exists. In common with MS- DOS code page 850 is this sign to find the position 238dec.

The overline is called, among other reasons often misspelled as " macron ", but should not be confused with the other Unicode characters of this name. The characters on the Kodepunkten U 02 C9 ( modifier letter macron ) and U 0304 ( combining macron ) are significantly shorter than their designated with overline counterparts.

The symbols denoted by combining merge with the preceding letters (example: 0,1 ̅ ), whereas the code points U 00 AF and U 203 E ( overline ) always act as independent characters (example: 0.1 or 0.1 ~ ¯ ).

Use

Often, the overline is used to indicate the periodicity of a number. Since it is not always possible to format the number so that the overline is above a certain point, it is often so used: 3, ~ 3 (read: 3 period 3 ) for 3.333333333333 ... or 3.12 ~ 34 3.123434343434 ... (that is, the digits are behind the overline, are repeated periodically ). The overline indicates that the periodic part of the number is behind him.

Even in electronic documents, and in the labeling of statistical averages ( for example) is the over-bar application.

Production in Text Software

• In HTML documents, the characters can ~ ¯ (decimal ¯ ) and ̅ ( ̅ ) are generated.
• In TeX, a single character \ bar x or \ bar { x} be repainted longer sections with \ overline { ABC }, where spaces are as "\ " or umlauts than to write "\ ddot a".
• In Microsoft Windows, the characters can cross-program with the key sequence Alt 0175 to insert. A single character can be painted by pressing Alt 0773 after entering the character.

Longer swept texts such as in 0,123 can be generated in some word processors as typestyle as a special form of underlining. In HTML documents, a style sheet statement such as 0, be applied 123 < / span>.