Conclusion

This thesis has described and evaluated a system that allows the freehand entry of formulae using a pen and tablet. After entering the formula, it is easy to arbitrarily manipulate it: rearranging, adding or deleting symbols. Once the user has entered the formula to their satisfaction, the system can then generate the corresponding L^ATEX command string. This command string can then be copied and pasted into the user's L^ATEX document.

In addition to combining an existing character recogniser and formula parser with new user interface ideas, this thesis has made a number of contributions:

• An algorithm for automatically grouping the user's strokes into symbols, using the character recogniser to evaluate different possibilities.

• New user interface concepts for identifying misgrouped and misrecognised symbols using annotated bounding boxes, and lagging the recognition so as not to distract the user.

• A ``squiggle select'' for correcting stroke grouping errors, allowing the user to draw a line through the strokes of symbols that should belong together.

• Showing that a graph rewriting parser has the potential to work well for handwritten input, although this particular implementation did not.

• Showing that a pen-based user interface for the entry and editing of mathematical formulae is desirable and preferable to existing command-string or template based entry systems.

A pen-based approach provides a more natural and familiar interaction method than existing command-string or template-based equation editors. When entering a formula using this system, a user does not have to learn a special language or notation; more importantly, they do no