Formula Library - Obsidian Plugin

中文文档 | English Doc

A LaTeX formula editor for Obsidian with MathLive WYSIWYG editing, 2100+ categorized formulas, smart search (pinyin, LaTeX commands, fuzzy matching), and extensible formula folders for user customization.

Features

• MathLive Visual Editor: WYSIWYG formula editing with real-time preview and virtual keyboard
• 2100+ Formulas: 18 categories (Greek, Structures, Delimiters, Analysis, Algebra, Geometry, Topology, Number Theory, Relations, Operators, Big Ops, Arrows, Sets, Functions, Probability, Physics, Chemistry, Misc)
• Smart Search: Pinyin initials, LaTeX command aliases, word-based English matching, abbreviation matching (e.g., "lt" → less than), and fuzzy matching
• Usage Frequency Sorting: Formulas you use most appear first — search results and category lists are sorted by insertion count
• Favorites: Star any formula for quick access. Favorites filter in sidebar and editor modal, always sorted to the top
• Configurable Shortcuts: Custom keyboard shortcuts for fraction, sqrt, superscript, subscript (default: unbound)
• Matrix Templates: cases, matrix, bmatrix, pmatrix, jacobian, hessian, identity, diagonal, augmented
• Visual / Source Mode: Toggle between WYSIWYG and raw LaTeX editing
• Edit Existing Formulas: Place cursor inside $...$ or $$...$$ and run command to edit
• Sidebar Quick Insert: Click formulas in the sidebar to insert directly
• Group Dropdown: Category selector as dropdown for compact sidebar layout
• Settings Page: Language, insert format, editor mode, shortcuts, font size, font style, formula group toggles
• Extensible Formula Folders: Add custom formula groups by dropping JSON files into formulas/
• Bilingual: Full Chinese/English localization, follows Obsidian language setting

Installation

Manual

1. Copy obsidian-formula-library folder to your Vault's .obsidian/plugins/ directory
2. Enable in Obsidian Settings > Community Plugins
3. (Optional) Set a hotkey for "Open Formula Editor" in Settings > Hotkeys

BRAT

1. Install the BRAT plugin in Obsidian
2. Open BRAT settings, click "Add Beta plugin"
3. Enter: strangelion/obsidian-formula-library
4. Restart Obsidian after installation

Usage

Formula Editor

• Command Palette: Ctrl+P → "Open Formula Editor"
• Ribbon Icon: Click the Σ icon on the left
• Select a formula category on the right, click a formula to insert into the editor
• Click Insert (or Shift+Enter) to write the formula to your note

Sidebar Quick Insert

• Click the Σ icon to toggle the sidebar
• Use the dropdown to switch categories
• Click ☆ to favorite a formula, click ★ to unfavorite
• Click a formula to insert directly at cursor position
• Most-used formulas appear first in each category

Edit Existing Formulas

• Place cursor inside $...$ or $$...$$
• Run command "Edit Formula at Cursor"
• Modify and click Update

Formula Categories

Category	Count	Description
Greek	52	α, β, γ, ...
Structures	43	Fractions, roots, integrals, sums, matrices
Delimiters	36	Parentheses, brackets, braces, absolute value
Analysis	210	Real/complex/functional analysis, measure theory
Algebra	174	Linear algebra, group/ring/module theory
Geometry	133	Classical, differential, Riemannian, symplectic
Topology	166	Point-set, algebraic, differential
Number Theory	166	Elementary, analytic, algebraic, modular forms
Relations	112	Equalities, order, subsets, logic
Operators	64	Arithmetic, set, logic operators
Big Ops	20	Sums, products, integrals, unions, intersections
Arrows	68	Various arrow symbols
Sets	40	Set theory, logic, cardinals
Functions	131	Elementary, special functions, distributions
Probability	170	Distributions, theorems, stochastic processes
Physics	251	Mechanics, EM, quantum, relativity, QFT
Chemistry	229	Reactions, molecules, ions, thermodynamics
Misc	56	Ellipsis, infinity, special symbols

Custom Formulas

Formula data is stored in the formulas/ folder inside the plugin directory, with one JSON file per category. Users can add new formulas or categories directly.

BRAT Compatibility: The plugin includes embedded fallback data in main.js. If the formulas/ folder cannot be loaded, the plugin automatically uses the fallback. When releasing, include the entire formulas/ folder in your release assets.

File Structure

formulas/
  _index.json          # Category ordering (optional, auto-discovered if missing)
  _strings.json        # UI translation strings
  greek.json           # Greek letters
  structures.json      # Structures
  analysis.json        # Analysis
  ...                  # Other categories

Adding Formulas to an Existing Category

Edit the corresponding JSON file and add new formulas to the items array:

{
  "id": "greek",
  "structures": false,
  "items": [
    ["α", "\\alpha"],
    ["β", "\\beta"],
    ["Custom", "\\mycommand{#?}", "Custom Formula"]
  ]
}

Adding a New Category

1. Create a new JSON file in the formulas/ directory (e.g., mycategory.json):

{
  "id": "mycategory",
  "structures": false,
  "items": [
    ["Formula Name", "\\latex{code}", "English Name"]
  ]
}

2. Add the category ID to the order array in _index.json:

{
  "order": ["greek", "structures", "...", "mycategory"]
}

If _index.json doesn't exist or doesn't include the new category ID, the plugin auto-discovers and loads groups alphabetically.

Formula Format

Each formula is an array: [label_zh, LaTeX code, label_en (optional)]

• Simple: ["α", "\\alpha"]
• With English label: ["Fraction", "\\frac{#?}{#?}", "Fraction"]
• Section marker: {"section": "Section Title", "sectionEn": "Section Title"}
• Matrix template: ["Matrix", "matrix:matrix", "Matrix"] (prefix matrix: triggers template)

Development

# Syntax check
node -c main.js

Acknowledgments

Formula library extracted from LaTeXSnipper Office Plugin Rendering uses Obsidian's built-in MathJax and MathLive