preamble subsection

The optional preamble subsection supplies LaTeX code that is injected into the generated document immediately before \begin{document}. It accepts three forms.

String form (literal LaTeX)

A plain YAML string is inserted verbatim:

document:
  preamble: |
    \setmainfont{Lato}

This form gives full control but suppresses all pygacity defaults — nothing extra is added.

Absent / null

If preamble is omitted entirely, pygacity applies its built-in defaults: the default font and the default pagestyle (see below).

Structured dict form

The most flexible form is a mapping with up to four sub-keys: font, pagestyle, colors, and commands. Each is optional; font and pagestyle default to "default" when absent.

document:
  preamble:
    font: default
    pagestyle: default
    commands:
      Universityname: Drexel University
      Coursename: CHE 230 - Thermodynamics I

font

Controls the font preamble. Accepted values:

"default" (default when absent)

Loads TeX Gyre Heros via fontspec and sets it as the document default:

\setmainfont{TeX Gyre Heros}

literal LaTeX string

Any other string is inserted verbatim, e.g.:

font: \setmainfont{Lato}

dict with input key

Reads font preamble from a local file:

font:
  input: my_font.tex

~ (null)

Suppresses the default entirely — no font preamble is added.

pagestyle

Controls the page-style preamble. Accepted values follow the same pattern as font:

"default" (default when absent)

Sets up fancyhdr with the course name and serial number in the header and the page number in the footer:

\pagestyle{fancy}
\fancyhf{}
\lhead{\footnotesize \Universityname\ --- \Coursename\ --- \Termname}
\rhead{\footnotesize <<<serialstr>>>}
\rfoot{\thepage}

<<<serialstr>>> is replaced by pygacity at build time with the document’s serial-number string.

"single"

A minimal page style suited to single-page documents (singlets):

\pagestyle{fancy}
\fancyhf{}
\chead{\sc{singlet}}
\rfoot{\thepage}

~ (null)

Suppresses the default — no page-style setup is added. Use this when your document class handles headers and footers itself.

colors

Controls an optional color / hyperref configuration block. Accepted values follow the same pattern as font:

"example"

Loads the bundled example color configuration (Drexel blue/yellow palette with hyperref link colours).

literal LaTeX string or dict with input key

As for font above.

~ (null, default)

No color preamble is added.

commands

A mapping of autoprob class variable names to values. Each entry becomes a \renewcommand in the preamble:

commands:
  Universityname: Drexel University
  Departmentname: Chemical & Biological Engineering
  Instructorname: A. N. Other
  Instructoremail: ano@drexel.edu
  Coursename: CHE 230 - Thermodynamics I
  Termcode: 202535
  Termname: Spring 2025

Only commands that are defined as zero-argument \newcommand entries in autoprob.cls are permitted. pygacity raises a ValueError at startup if an unknown command name is supplied.

Typical full example

This is the pattern used by the bundled examples — suppress the built-in font and pagestyle so they are fully controlled by the commands block and any additional LaTeX in the class:

document:
  preamble:
    font: ~
    pagestyle: ~
    commands:
      Universityname: University of Nowhere
      Departmentname: Mechanical Engineering
      Instructorname: Eustace T. Smartypants
      Instructoremail: ets@unow.edu
      Coursename: BIO 5678 - Applied Pyrohydrodynamics
      Termcode: 202525
      Termname: Winter 2025-2026