System for parsing multidimensional and multidirectional text into encoded units and storing each encoded unit as a separate data structure

Claims

What is claimed is:

1. In an information processing system including a keyboard, a display device, and an editing means, coupled to said keyboard and said display device, for editing both multidirectional and multidimensional text, the editing means comprising:

memory means storing instructions for editing text, said text including said multidirectional and multidimensional text;

input receiving means responsive to keystrokes from said keyboard representing text characters and editing commands for generating a string of codes defining a text;

parser means responsive to said string of codes from the input receiving means and said instructions in said memory means for:

reading the codes of the string and parsing the codes into encoded units, each of said encoded units being stored in said memory means as a data structure, each said encoded unit defining a different group of one or more characters and at least one of said encoder units defining a group of two or more characters that are positioned in an expression as a unit, said unit being delineated by predefined characters, and being comprised of codes which define the group, and

generating for each said encoded unit a unit structure and storing said unit structure in said memory means, wherein each said unit structure is comprised of a data structure that contains information defining a visual representation of the corresponding encoded unit, said visual representation being such that said multidirectional text and said multidimensional text are represented for visual display; and

display means for receiving and displaying said visual representation information from said memory means on said display device.

2. The text editing means of claim 1, wherein:

the parser means is further responsive to operation of the input receiving means for

reading unit structures and corresponding codes of the string and generating a visually displayable representation of the text.

3. The text editing means of claim 1, wherein the codes in the string of codes representing a text include:

character codes representing the characters of the text, and

operator codes defining properties of the text other than the characters from which it is constituted.

4. The text editing means of claim 3, wherein the operator codes comprise:

prefix operators operating upon a following character, group of characters or unit or group of units,

postfix operators operating upon a preceding character, group of characters or unit or group of units, and

infix operators operating concurrently upon two characters, groups of characters or units or group of units.

5. The text editing means of claim 4, wherein an infix operator operates to define a relationship between the two characters, groups of characters or units or group of units operated upon by the operator.

6. The text editing means of claim 5, wherein an infix operator occurs in the string of codes between the two characters, groups of characters or units or group of units operated upon by the operator.

7. The text editing means of claim 3, wherein the operator codes comprise:

structural operators defining organizational relationships between the units, and

environmental operators defining attributes of the characters.

8. The text editing means of claim 7, wherein the structural operators comprise:

unit operators defining spatial relationships between units of the text.

9. The text editing means of claim 8, wherein the structural operators comprise:

initiating operators initiating corresponding units defined by the operators, and

corresponding terminating operators terminating the units initiated by the initiating operators.

10. The text editing means of claim 7, wherein the structural operators comprise:

associative operators defining an association between a character and another character such that

the character becomes a part of the definition of the other character.

11. The text editing means of claim 10, wherein the associative operators include:

diacritic operators which operate to signify a correspondence between a diacritic mark of the text characters with a base character of the text characters.

12. The text editing means of claim 7, wherein the environmental operators comprise:

attribute switching operators which operate to turn on or turn off a corresponding attribute.

13. The text editing means of claim 7, wherein the environmental operators comprise:

attribute modification operators which operate to modify a continuously existing attribute.

14. The text editing means of claim 3, wherein the operator codes comprise:

script operator codes, wherein

each script operator code defines a script unit of the encoded units located in a script position with respect to a base unit of the encoded units.

15. The text editing means of claim 14, wherein each script unit is defined as a unit having a baseline oriented with respect to the baseline of the base unit and offset from the baseline of the base unit by a selected distance and wherein the location of the script unit baseline relative to the base unit is determined by the script operator code.

16. The text editing means of claim 15, wherein the baseline of the script unit may be offset to either side of the baseline of the base unit.

17. The text editing means of claim 16, wherein the script is located in a position

preceding the base unit,

centered on a line passing vertically through the base unit, or following the base unit.

18. The text editing means of claim 15, wherein the script unit is located in a position

preceding the base unit,

centered on a line passing vertically through the base unit, or following the base unit.

19. The text editing means of claim 15, wherein the script operators include operators for a presuperscript, above script superscript, presubscript, below script and subscript locations.

20. The text editing means of claim 15, wherein the operator codes include:

line split operator codes, wherein

each line split operator code defines a group of N units wherein the group of N units are arranged along a line oriented at right angles to a baseline.

21. The text editing means of claim 20, wherein the group of N units are centered about the baseline.

22. The text editing means of claim 20, wherein the group of N units are centered about a line split starting location which is offset with respect to the baseline.

23. The text editing means of claim 22, wherein the baseline of the script unit may be offset to either side of the base unit.

24. The text editing means of claim 23, wherein the script unit is located in a position

preceding the base unit,

centered on a line passing vertically through the base unit, or following the base unit.

25. The text editing means of claim 22, wherein the script unit is located in a position

preceding the base unit,

centered on a line passing vertically through the base unit, or following the base unit.

26. The text editing means of claim 3, wherein certain ones of the operator codes include associated parameter codes further defining the operation to be performed.

27. The text editing means of claim 3, wherein certain ones of the operator codes are terminator codes which operate to terminate a preceding operator code.

28. The text editing means of claim 1, wherein each unit structure further comprises:

structural identification fields containing information relating the unit structure to the group of codes in the text string comprising the encoded unit corresponding to the unit structure.

29. The text editing means of claim 28, wherein the unit structure further includes:

structural flag fields containing information identifying a reason the present unit is separated from the parent or preceding unit.

30. The text editing means of claim 1, wherein each unit structure further comprises:

structural pointers information fields containing information identifying other unit structures associated with the unit structure.

31. The text editing means of claim 1, wherein each unit structure further comprises:

property identification fields containing information defining attributes which apply to the characters or symbols of the corresponding encoded unit.

32. The text editing means of claim 31, wherein the information residing in the property identification fields includes information describing the location and dimensions of the unit on a page.

33. The text editing means of claim 32, wherein the location and dimensional information residing in the property identification fields includes information identifying dimensions of all script, line split and bar units associated with the unit.

34. The text editing means of claim 1, wherein each unit structure further comprises:

a location field containing information identifying the location of the corresponding encoded unit within a page of text that is currently being edited.

35. A computer implemented method performed by an editing means for editing and displaying text including both multidimensional and multidirectional text in an information processing system including a keyboard, a display device, and said editing means coupled to said keyboard and said display device, said editing means including memory means, input receiving means, parser means, and display means; said method comprising the steps of:

a) receiving by said input receiving means a stream of said text as input from said keyboard, said text including said multidimensional and said multidirectional text;

b) generating by said input receiving means a string of codes defining said text;

c) reading the codes of the string and parsing said codes into encoded units by said parser means, each of said encoded units being stored in said memory means as a data structure, each said encoded unit defining a different group of one or more characters and at least one of said encoder units defining a group of two or more characters that are positioned in an expression as a unit, said unit being delineated by predefined characters, and being comprised of codes which define the group;

d) generating by said parser means for each said encoded unit a unit structure and storing said unit structure in said memory means, wherein said unit structure is comprised of a data structure that contains information defining a visual representation of the corresponding encoded unit, said visual representation being such that said multidirectional and said multidimensional text are represented for visual display; and

e) displaying by said display means on said display device said visual representation information from said memory means.

CROSS REFERENCES TO RELATED APPLICATIONS

The present patent application is related to the following U.S. patent applications:

______________________________________ U.S.S.N. Filing Date ______________________________________ 846,667 3/31/86 879,700 8/8/86 879,729 6/27/86 880,607 10/14/86 122,615 11/19/87 ______________________________________

All of the above patent applications have been abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to text editors and, more particularly, to a text editor allowing word processing like operation with multidimensional or multidirectional text, such as text comprised of scientific and technical characters and symbols, including those used in the mathematical, physical and chemical fields, and the text of non-European languages.

2. Discussion of the Prior Art

The most common means for presenting, communicating and storing information is through visual representations of the information, for example, printed texts and images and, more recently, through equivalent electronic displays such as CRT screens connected from computer systems. In recent years, the facility with which texts and graphics images can be created and edited and printed, communicated and stored has been greatly facilitated by various word processing and graphics editor programs operating upon computers system. Both word and graphics processing systems have become well known and are readily and commonly available to the extent that practically any reasonable user requirements of system, features, operation and cost can be readily met.

A recurring problem with such systems, however, is that each type of system, that is, word processing or graphics processing, can operate only within a narrow range of information type and presentation. For example, word processing systems generally can operate only with standard text of the forms generally used in the European languages, such as English, that is, standard alpha-numeric characters of uniform, standard sizes and shapes arranged on a page in standard lines and columns to form lines and paragraphs. Within this constraint, however, the word processing programs are generally quite efficient and easy to use. Graphics programs, in contrast, deal with symbols and figures of variable shapes and sizes and their visual appearance and location upon a page. Such programs provide a means by which a user may define shapes and their sizes and locations upon the page and may place, move and change such shapes but are relatively more difficult for a user to learn and use.

This separation between word processing and graphics processing programs arises because the word processing data structures and data structure editors which are best adapted for creating and editing standard text are incompatible with the graphics data structures and data structure editors which best adapted to creating, editing and representing graphics symbols and figures. As described above, word processors are designed to operated with simple strings of standard, uniform elements arranged within a fixed array of possible locations on a page while graphics processors deal with variable lines and shapes which may be located anywhere on a page.

There is an area of information processing and presentation, however, which is neither strictly word processing nor strictly graphics processing and which is not adequately satisfied by systems of either of the types described above. This area of information processing and presentation may be generally defined as being comprised of those forms of text which are either multidimensional or multidirectional, or both. A primary and commonly seen example of such text is scientific text and symbols in the traditionally accepted forms, for example, equations, expressions or diagrams as used in the mathematical, chemical or physical fields and using the symbols and terms used in these fields. Other example, as previously described, include those languages wherein the text, that is, the positioning of the characters and symbols on the page and their logical and physical relationships to one another do not follow the one dimensional, monodirectional conventions of, for example, English, German, French or Italian. Examples such such foreign language texts may include the branches of the Indic language groups, such as used in India, and the texts of such countries as Sri Lanka, Burma, Thailand, and such languages as Chinese, Japanese and the various branches of the Arabic languages.

It is apparent from a study of a page of a text of this nature, for example, a page of scientific text, that the text is comprised of logical groupings of one or more character or symbol elements arranged in a meaningful manner relative to one another. It is further apparent, however, that the characters and symbols are of variable shape and size and that their locations relative to one another are also variable. It is yet further apparent that the geometric area occupied by a group of characters or symbols, and the location of that area on a page, will be determined by the structure of the group of characters or symbols and of the other groups of characters or symbols on the page, in particular the preceding groups on the page and perhaps the following groups on the same line.

In the prior art, the editors for such texts have generally fallen into one of the two types described before, that is, the word processing type or the graphics processing type. In the word processing type of text editor of the prior art, the editors have most frequently been adaptations of simple word processors, with some addition of characters and symbols to the standard character sets and formatting commands. This type of word processing text editor has been unsatisfactory because of the limited powers of expression available therefrom. That is, the characters and symbols are forced into the standard character sizes and proportions and may occupy only the positions generally provided in word processing, for example, simple superscripts and subscripts. Some word processing type text editors have attempted to provide a wider range of characters, symbols and expression, but have been markedly more difficult to use and generally cannot provide a representation of the appearance of the final page to the user during the creation and editing operations. That is, the wider range of expression is achieved by embedding control codes in the text during text creation and editing, but the user must actually print the page to have a representation of the true appearance of the page.

While graphics processing systems are much more flexible than word processing type systems in terms of the range of characters, symbols and expressions which may be created and presented, they are generally much more difficult to use, primarily because of their greater flexibility. In effect, the user must draw each individual character, symbol or line individually, or at least create a template of each type to appear in an expression, and then must position each character, symbol or line individually on the page. In terms of text editing, this approach is little better than having a template of characters and symbols, a piece of paper and a pen.

As will be described in the following, the text editor of the present invention overcomes these and other problems of the prior art by providing a text editor having a word-processor-like document creation and editing functionality together with a graphics-like visual representation suitable for creating and editing text and expressions which are multidimensional or multidirectional, or both, in their traditionally accepted forms, for example, equations, expressions or diagrams as used in the mathematical, chemical or physical fields and using the characters, symbols and terms commonly accepted and used in the