Although there is an equation editor in * PowerPoint*, it is not
very powerful, and lacks such rudimentary features as the ability to
change the colours of the equation. * Showcase* has no equation
editor at all. However, there is fortunately a simple solution to
this. There are two programs on the SGI, one called *
equationtopict*, and the other * equationtorgb*.

As might be expected, * equationtopict* creates a Macintosh PICT
from an equation description, while * equationtorgb* creates an
IRIS RGB. The equation description is identical to that used in
LaTeX. Please see the LaTeX documentation for further details on
how to describe equations. As an example, the following description
of an equation could be saved in a file called
`equation.tex`

:

S_{xx} = \frac{1}{2} \left( \frac{\partial u_x}{\partial x} + \frac{\partial u_x}{\partial x} \right) = Kwhich corresponds to the expression:

Please note that the input file to * equationto** contains only the
equation description. It does not contain * any* other LaTeX
commands.

The colours of the equation are specified on the command line to *
equationto**. Colour specifications follow the format specified in
the manual page for * pgmtoppm*. Type `man pgmtoppm`

for
further details. Basically the colours are specified using their red,
green, and blue components. Unfortunately, the value of these
components is specified in hexadecimal notation, which is more
difficult for those of us without 16 fingers. For example, to create
an RGB of the above equation with a black background and yellow
foreground:

equationtorgb equation.tex equation.rgb #FFFF00 #000000where

`#FFFF00`

represents yellow, and `#000000`

represents
black.

Mark Wolforth (wolforth@bic.mni.mcgill.ca)