Logical Combinations in Filter Expressions

The lists displayed in the bookmark tool, in the spectral collection and in the database tool can be narrowed down by filter expressions. The functionality of these filters can be switched between plain substring search and more elaborate logical search (see option "Filter Mode for Text Filters" in the preferences). In the case you activated the logical search the following rules apply:

The filter expression may consist of any number of substrings which can be combined by various logical operators (AND, OR and NOT). Parantheses may be used to adjust the operator precedence. The substrings can contain the following characters: the digits '0..9', the characters 'a..z', 'A..Z' and '_', the German umlauts 'äöüÄÖÜ', and the German 'ß'. All other characters are not allowed and result in an "invalid search expression" warning.

The logical operators are represented by the following single-character symbols:

Operator Symbol
AND + (plus)
OR , (comma)
NOT ~ (tilde)

Following are a few examples of valid filter expressions:

Expression Explanation
(wine,water)+taste either "wine" or "water" and "taste" are required to be part of the search string
(wine+milk),water both "wine" and "milk", or "water" are part of the search string
micro+~processor "micro" but not "processor" are part of the search string