音声ブラウザご使用の方向け： SKIP NAVI ／ GOTO NAVI

TRIANGLE: TRI-MODAL ACCESS TO TEXT, TABLES, EQUATIONS, GRAPHS, CALCULATIONS, AND FIGURES

Hadi Bargi Rangin
Steve Sahyun
Randy Lundquist
and John Gardner
Oregon State University

Web Posted on: November 22, 1997

1. Introduction

TRIANGLE is a DOS computer program intended for print-impaired students and professionals in math, science, and engineering. It includes:

  • a math/science word processor,
  • a graphing calculator,
  • a viewer for y versus x plots,
  • a table viewer,
  • The Touch-and-Tell Program for audio and/or braille-assisted reading of tactile figures on an external digitizing pad.

The keyboard or any assistive device/software that emulates a keyboard may be used for input. TRIANGLE output may be viewed:

  • Visually on the DOS text screen,
  • Audibly using a screen-reading program and external voice synthesizer for text and the PC speaker or an SB16 compatible sound output for other audio,
  • Tactually using a braille screen access program and external refreshable braille display,
  • Any or all of the above simultaneously.

TRIANGLE has an on-line help file describing all editing, calculator, graph-viewing, table-browsing, and figure-reading commands. Several tutorials are also included with the distribution files.

TRIANGLE is still in a beta stage and is available to anyone interested in trying it.[1] The expanded symbol set used with the mathematical word processor can be accessed with DOS screen readers only if the appropriate character tables are installed. Support is included for Vocal-Eyes speech screen reader and TSI braille displays. Instructions are included for use with other screen readers, but some expertise and effort on the part of the user is required. TRIANGLE menus and help files are in English, but the program should work with most other languages that use the roman alphabet.

2. The TRIANGLE mathematical word processor

The TRIANGLE word processor is somewhat similar to the standard Microsoft DOS[2] text processor "edit.com" but with an expanded character set. The expanded characters include most of the symbols used in elementary, high school, and undergraduate math and science. Virtually any math and scientific symbol can be represented with symbol modifiers and special construction indicators included in the TRIANGLE symbol set. These symbols are stored in ASCII positions supported by DOS but not included in the 95 "printable" characters.

The symbol set also includes "mark-up" symbols that allow one to indicate subscripts, superscripts, fractions, etc. in a compact linear form.

Expressions may be entered and manipulated with the usual kinds of editing capabilities found in any text processor. There are four independent text buffers and a "scratchpad" buffer used by the calculator. TRIANGLE uses a clipboard for cutting and pasting that is manipulated by commands similar to those in MS DOS applications. In addition, it has ten specially-addressable clipboards that allow a user to cut and paste several things without losing the last one every time a new item is saved. This facility provides significantly increased flexibility that is handy when manipulating math, solving algebraic equations, etc.

The word processor is accessed through a voice or braille screen reader. However, it is necessary to provide the screen reader with a table identifying the extended symbols. For speech access methods, the expanded symbols must be loaded into an appropriate character definition table; no change is required for the conventional printable ASCII characters.

Braille access poses a different problem, since there is no "accepted" braille representation for anything except letters. We have adopted the 8-dot version of the GS braille representation[1] in TRIANGLE. GS is a dual 6/8-dot representation developed by John Gardner and Norberto Salinas (Prof. of Mathematics, University of Kansas). GS was inspired by the current on-going unified braille code (UBC) development effort by the International Committee on English Braille. GS adopts the UBC philosophy of retaining as much as possible of current literary braille. TRIANGLE includes a GS tutorial for braille users.

The current beta version of TRIANGLE includes character files and a profile file intended to be used with the Vocal-Eyes 2.2 or 3.0 speech screen reader. A GS braille file is included for the popular TSI on-line computer braille displays.

3. The TRIANGLE graphing calculator

TRIANGLE includes the equivalent of a scientific graphing calculator. One may do a numerical calculation by entering an expression in any of the word processor buffers and then selecting it and pressing function key F4, which is the "evaluate expression" key. The calculator allows the user to input or define constants for convenience and accepts several types of notation for operations - e.g. one can use a GS multiply symbol or the * which is commonly-used to indicate multiplication on computers.

The result of the computation is given in the scratchpad buffer, and focus changes to that position after the calculation. The results may be copied and pasted to other buffers.

A function is graphed by first defining the range of the independent variable and the number of points to be computed, then writing the function to be computed, and finally pressing function key ALT-F4, the "evaluate and plot" key. The function is computed, sent to the x-y graph viewer, and then focus shifts to that viewer.

4. The TRIANGLE x-y graph viewer

A function is scaled so that it can be displayed as a low-resolution picture on a DOS text screen. It is "viewed" audibly by a blind user through a tone plot. The user may move a pointer along the independent variable axis, and the value of the function is indicated by the pitch of a tone. The function is scaled so that the full range from the minimum and maximum of the function corresponds to a pitch well within the normal range of human hearing. The function is also displayed as a moving icon on the bottom line of the screen. As the pointer is moved along the independent-variable axis, the icon moves to the right as the function becomes larger and to the left as it becomes smaller. This icon is primarily intended for deaf blind users who would view it with an on-line braille display.

The pointer may be moved one point at a time or allowed to scan automatically from left to right and from right to left. The values of the independent variable and of the function are displayed and may be read with the screen reader. The viewer functions include the ability to find both relative and absolute maxima and minima, zeros, etc. The simple tone reader gives a reasonable qualitative overview, and a user may look individually at various points for quantitative information. Finally the plot may be printed in low resolution on any braille printer that has a TSI Versapoint braille graphics emulator.

5. The TRIANGLE table viewer

Tables may be included as part of a text file or saved as table files with a defined file extension. In either case, they should be marked up with the GS markup indicators that tell where the table begins and ends and where each element and line ends.

The table view has two modes. A formatted mode is intended primarily for small tables being read using an on-line braille display. In this mode, tables are displayed on the screen much as they would be if formatted for sighted readers.

The formatted table mode is clumsy if the table is large or if the user is reading with a speech synthesizer. The cell-by-cell mode is intended for such cases. The reader views one cell at a time and can navigate right and left, up and down from cell to cell in the table. The screen also shows the title and the cell row and column number. Optional information such as the row or column labels may also be displayed. This mode permits blind readers to read extremely large or complex tables as long as the information in all cells is readable.

The table viewer may be entered at will, and a table remains in the viewer until it is replaced by another one. Tables appearing in the text may be captured into the reader by placing the cursor anywhere within the table and pressing Function key ALT-F5, the "capture table" key.

6. The TRIANGLE Touch-and-Tell figure viewer

This feature requires use of an external digitizing tablet on which a tactile figure is mounted. A computer "map" file is required, so that whenever a user identifies an object on the figure, the computer can display information about that object. The information is read with the screen reader and can be up to 32 kilobytes in length.

The figure viewer can be entered at will, and once a map file is read in, the figure is scaled by indicating marks at the top right and bottom left of the figure. This information remains until a new figure is mounted and a new map file read into the table viewer.

7. Preparing materials for TRIANGLE

Both sighted and blind users can create scientific documents in the word processor, save expressions to be computed and graphed, and create tables in the table viewer. It is possible in principle to translate these to the page-setting language LaTeX and print them for sighted people. A GS to LaTeX translator is being written but is not yet available.

It is also possible in principle to create TRIANGLE files from well-structured electronic files of other kinds. A restricted LaTeX to GS translator will be developed that allows LaTeX to be translated to GS. We already have a program[3] that translates LaTeX tables to GS format. The program also translates Lotus[4] 1-2-3-format tables to GS.

A sighted person can create tactile figures and the accompanying computer map files with our Objectif[1] program. Objectif runs under Microsoft Windows[2] and permits a sighted person easily to edit and simplify a bit mapped image file to print on swell paper or a braille graphics printer. The map file is created by selecting objects on the computer screen and entering labels or any desired text information to be displayed when the blind user selects that object. At present there is no way for a blind user to create TRIANGLE figures and map files.

8. Acknowledgments

The research at Oregon State University was supported by National Science Foundation grant HRD- 9452881.

9. References

[1] Up-to-date information about TRIANGLE and Objectif is maintained on the Science Access Project web site http://dots.physics.orst.edu

[2] Microsoft DOS and Microsoft Windows are registered trademarks of Microsoft Corporation.

[3] "GS2LaTeX" will soon be made available on the Science Access Project web site http://dots.physics.orst.edu

[4] Lotus 1-2-3 is a registered trademark of Lotus Development Corporation.

Go to the top of this page. | Go to the upper category.