Abstract: A process and apparatus for recalculating the contents of a spreadsheet's cells when they are affected by a modification of one or more cells in the spreadsheet is disclosed. After a spreadsheet has been modified, each cell in the spreadsheet is examined only once to determine the order of the cell recalculation and only the affected cells are recalculated. A list indicating which cells have been modified is maintained at all times in the computer prior to recalculation. When the computer is instructed to update the values in the spreadsheet cells, the recalculation method begins by placing an indication of cells affected by modification, one by one, on either of two lists independently maintained by the computer in storage: the final list (L LIST) if all cells in its Dependency Set (the set of cells affected by a modification to this cell) are already in the final list, or the intermediate list (R LIST) if it has a cell in its Dependency Set which is not already in the final list.

Abstract: A method and apparatus carried out on a digital computer for creating and editing mathematical equations in a printed document is disclosed. This invention allows the user of a wordprocessing program to create and edit mathematical equations in an efficient and flexible manner through use of a user interface which includes an editing window, a display window, and a palette window. The editing window allows the user to input a textual description of the equation, the palette window provides an alternative method of entering the textual description of the equation by displaying the characters and commands that may be used, and the display window displays the equation as it appears in its final printed form.

Abstract: A method and apparatus for utilizing a digital computer to print characters of multiple fonts, both textually and graphically, on a single printer from within a single document [is disclosed]. Existing computer programs provide the capability of printing pre-defined textual characters or graphical characters separately, but not in an integrated manner as is disclosed. Thus, the invention enables printing of a variety of mixed characters, such as international alphabetic characters and complex mathematical characters, within a single document.