The QWorld Package

Overview

QWorld is a LaTeX package designed to simplify the drawing of complex graphical calculus in monoidal category theory. This package provides a concise and intuitive set of commands, allowing users to efficiently render string diagrams with minimal effort. This package is particularly useful for researchers working in category theory, quantum theory, and related fields where diagrammatic reasoning plays a crucial role.

Installation

Once the package is available in a TeX distribution via CTAN, you can use it in your document by adding:

\usepackage{qworld}

Alternatively, to install it manually:

1. Download the package's .sty file.
2. Place it in your LaTeX working directory or an appropriate directory within your TeX distribution.
3. Add usepackage{qworld} to the preamble of your document.
4. Run texhash if necessary to update the file database.

Usage

Below is a basic example of how to use qworld

\documentclass{article}
\usepackage{qworld}

\begin{document}
  \[
    \q{
      \qcap\qwire\n
      \qwire\qcup
    }=\q{
      \qwireup[vlen=2]
    }
  \]
\end{document}

For more detailed usage instructions, refer to the package documentation.

License

This package is distributed under the LaTeX Project Public License (LPPL), version 1.3c or later.

Copyright

© 2025 Niina Ryota

This Package consists of the following files:

• qworld.sty (the main package file)
• qworld.pdf (documentation compiled from qworld.tex)
• qworld.tex (LaTeX source file for documentation)
• qworld_en.tex (LaTeX source file for the English version of the documentation; compiled into qworld_en.pdf)
• qworld_en.pdf (compiled English documentation; English version of qworld.pdf)

The current maintainer of this package is Niina Ryota.

Modification Policy

Under the terms of the LPPL:

• Any modifications must not be distributed under the original package name.
• Any modified versions must clearly state that they are derived from this package.
• The original author (Niina Ryota) must always be credited in derived works.

Contact

Author: Niina Ryota Email: qworld-package@googlegroups.com

Change Log

1.1.1 (2025-04-14)

• Color annotation for wires and tangles
  • The frame color attribute is now supported for CAP and CUP structures, allowing wires to express object identity through color.
  • Additionally BRAIDING now supports separate L color and R color options for independently coloring the left and right wires.
• Improved wire rendering
  • The rendering of curves has been refined to produce smoother and more aesthetically coherent diagrams.

### 1.1.0 (2025-04-03)

• Argument structure revised for symbol commands
  • The following commands were updated to support key-value-style optional arguments instead of mandatory positional arguments:
    • \symbolI
    • \symbols
    • \symbolS
    • \symbolO
    • \symboln
    • \symbolN
  • Specific changes:
    • Old format: \symbolI[i]{ID}{text}[position options]
    • New format: \symbolI[i]{text}[position opotions, id=ID]
  • With this revision, the ID parameter is now optional. In simple cases, \symbolI{text} suffices. This change enables more concise and readable definitions.
• English documentation
  • An English version of the user guide has been added.

1.0.0 (2025-04-01)

• Initial release.

Contributions

Bug reports, feature requests, and contributions are welcome. Please contact qworld-package@googlegroups.com for inquires or to submit issues.