TeX equations in sndkit

This aims to provide a brief overview on generating inline equations in TeX.

Writing TeX Equations

The fig function in janet is used to generate an equation.

For example, this markup code:

@!(fig "tex_example" "y = mx + b")!@

Will produce the following equation:

The first argument is the name of the equation. This is used as the filename, so it should be unique (and without spaces). Typically the convention is to prefix it with the name of the algorithm it is in.

The second argument is the actual TeX code, written in math mode.

Small Equations

The smallfig function is used to render smaller equations, and is usually used for coefficients of an equation.

For example, the following markup code:

The equation above has the variables,
@!(smallfig "tex_y" "y")!@, @!(smallfig "tex_m" "m")!@,
@!(smallfig "tex_x" "x")!@, and @!(smallfig "tex_b" "b")!@.

This is the formula for a linear equation in algebra where
@!(smallfig "tex_y")!@ is the output,
@!(smallfig "tex_x")!@ is the input, @!(smallfig "tex_m")!@
is the slope of the line, and @!(smallfig "tex_b")!@ is
the offset.

Looks like this:

The equation above has the variables, , , , and .

This is the formula for a linear equation in algebra where is the output, is the input, is the slope of the line, and is the offset.

Note that the second argument in smallfig is optional, allowing figures to be easily re-used as seen above.

Rendering Equations

The next time weewiki exports HTML it will generate individual TeX code for all the equations in all the pages. These are located in the _figs directory.

The diagrams for this page can be explicitely generated running the following command in the top-level sndkit directory:

weewiki export tex > /dev/null

Then, go into the _figs folder.

Any time new figures are added, the figure list needs to be manually regenerated again with:

./mkfiglist > figs.mk

Running make without any arguments will generate all PNGs using TeX and the dvipng utility, which should be included with any texlive distribution. Two versions of the file will be included: a regular PNG file, and version with 2x the resolution for computers with HD displays.

Removing Figures

If a named figure gets removed, the corresponding TeX file must be removed from the _figs directory, and figs.mkregenerated with mkfiglist.