The graphical user interface is called &pyc;. It provides a simple access to the most common features of the underlying engine, &pyb; and lets you search, sort and modify bibliographic entries. When &pyc; is opened, you can immediately begin to create a new database. The type of this database will be determined when you will save it the first time. To add a new entry, you can use the Edit Add... menu, or click with the right button in the list window and select Add... You will find more information on the main window's usage in . To open an existing database, go in the File menu, and select File Open .

A file selection dialog will pop up (see ) and let you select a file name or enter an URL. The type of the database can also be selected. In the case of a new database, it is mandatory to select a type, whereas while opening an existing database, the type can be guessed if you select - Auto -. Once you have opened a database, or started to create a new one, the main window (see ) displays a list of all the entries on the top part of it. Clicking on an entry displays its full content on the lower part of the window. It is also possible to use the arrow keys to navigate in the upper list. Clicking on an entry while pressing the Shift key extends the selection to the clicked entry. A click while pressing the Control key toggles the entry without altering the state of the rest of the selection.

Clicking the right button of the mouse in the list opens a contextual menu. With this menu you can: add a new entry edit the currently selected items delete the currently selected items Note that some of these menu options can be disabled for a given database or entry, provided that the corresponding action can't be performed. By clicking on the column titles of the list, you'll sort the entries according to the corresponding field. &pyc; offers a quite powerful seraching mechanism. To open the search dialog, click on Edit Search in the menu. The dialog that appears (see ) displays a search form at the top.

With a simple search, you can select the field that will be searched and you can specify a regular expression to be matched. - any field - means that all the existing fields will be searched. This is usually more time-consuming. An advanced search is an expression that looks like: has('author','name') | -has('title','test') Such an expression means: select the entries where the field author matches name, or (symbol |) where the field title does not match test. The boolean and is noted &. There are other commands available for this type of search: has_key(keyname) searches on a key name. has_type(typename) searches for entries of a given type name. any_has(value) searches for the given value in all the fields of an entry. before(field, year, month, day) searches for entries where the specified date field is older than the specified date. after(field, year, month, day)searches for entries where the specified date field is younger than the specified date. After a search, only the selected items are displayed in the main window. It makes it convenient to select a specific author, and then browse its publications for example. In addition, the results of all the searches are kept in the tree located below the search form. Therefore, a new search can be a refinement of a previous one. If you select the tree item corresponding for example to all the articles written by a certain Nostradamus, you'll be able to select only those whose title contains the word eclipse. Right-clicking in this tree pops up a contextual menu that allows you to remove unuseful searches. Clicking on the title of each column in the main index provides some rudimentary way of sorting a database. A much powerful method is to open the sort dialog (in Edit Sort ). This menu, displayed in , gives a list of fields which can be used as sort criterions, plus a flag indicating how they are currently used. By clicking on the left column, it is possible to choose how the field will be used: Nothing means the field is not in use. A > symbol means sort in ascending order. A < symbol means sort in descending order. By clicking on the Reorder button, it is possible to group the activated fields on the top of the list, for a more convenient access. The order in which the sorting is performed depends on the order in the list. To modify this order, simply drag and drop an item to change its position.

The edition window is represented in . On the right of each field, a symbol indicates if &pyb; has been able to render all the information given in that field. For example, a BibTeX field containing an unknown command name cannot be correctly represented. In that case, &pyb; provides a fake representation (usually the name of the comand), and indicates it was not able to do a good job on this field by setting a red ball on its right, instead of a green one. If you edit such an entry, you can loose the additional information it contained. To avoid this, consider using native editing (see ). To edit the entries, simply type the corresponding text, without any consideration for the database format being used. For example, with BibTeX, don't add any { or special characters to influence the result, as they will be quoted by the system. For fields requiring names (like author and editor), use the following format: type one name per line, in the last name, lineage, first name order. The following keyboard shortcuts are available during edition (in addition to the standard ones provided by Gtk): Ctrl-TAB to jump to the next field Shift-TAB to jump to the previous field Ctrl-Enter to accept the modifications Escape to cancel the edition To specify a crossreference to another entry, just drag the entry from the main list to the Crossreference field. To remove a crossreference, drag an empty selection on the field. To unselect all the entries, you might need to use the Control key, while clicking on the entry. For databases like BibTeX that provide a specific syntax (called native syntax), it is possible to directly edit the entry in this format. Just click the button called Native Editing at the bottom of the window and type the entry in its native form. It is also possible to type native commands in the normal editing window. For example, if you want to use special LaTeX commands like \textbf in a title, you can type them directly in the Title field by preceding the text with a @ symbol (as the first character). After that symbol, you have to use all the BibTeX conventions (braces, backslashes,...), as none of them will be escaped or modified by &pyb;. It is possible to directly use &pyb; in order to insert bibliographic references into LyX. To do so, one first has to start the LyX server. In the configuration file ~/.lyx/lyxrc, add the following line before starting LyX: \serverpipe "~/.lyx/lyxpipe" Then, in &pyc;, it is possible to select one or several entries and insert their references into a running LyX simply by clicking the Cite button, or selecting the Cite Cite menu item. For the moment, it is the user's job to ensure that he/she inserts entries corresponding to the actual database being used. &pyc; does not handle the full job of bibliography generation; therefore it is necessary to use bibtex as described in the LyX documentation.