Quick Latex for Obsidian

【Now works with the new Obsidian preview mode!!】 【Custom shorthand NOT limited to 2-letters anymore～～ try multi-letters shorthand. e.g. inf -> \infty】

Description:

This simple plugin adds various shortcuts to speedup latex math typing.

Functionalities:

Note: All functionalities below can be toggled within the plugin settings page.

1. Auto close $ symbol + Move cursor between $$ symbols

• Typing $ will automatically close with $ and shift the cursor in between the $$ symbols.
• Tip: If you use the $ symbol often as currency symbol, you may toggle off the "auto close math symbol" function in the plugin setting.

2. Autoclose {}, [], () brackets

• Typing "{", "[" and "(" will automatically close with "}","]" or ")".
• Note: This function activates only when the cursor is followed by "$", space, tab, or nothing (end of line).

3. Auto append "\limits" after "\sum"

• Typing "\sum" will automatically append "\limits" to shorten the syntax for proper display of the limits for summation symbol.

4. Auto enlarge brackets that contains \sum, \int or \frac

• Place cursor right after a () or [] bracketed expression that contains either \sum, \int or \frac and press the space key, the outermost brackets will be appended with \left and \right in order to display larger brackets to enclose these big expressions. E.g. (\sum\limits_{i=1}^n x+1) => \left(\sum\limits_{i=1}^n x+1 \right)

5. Auto enclose expression after superscipt and subscript with {}

• Typing expressions after superscript "^" and subscript "_" symbol follow by a "space" key will automatically surround the expressions with "{}".
• NOTE: if you are use to typing subscript indexing without enclosing it with {}, there is high tendency that the autoEncloseSubscript function may miss fire when you press space after a subscript symbol not intended to be bracketed. In this case, its recommended to turn off this function.

6. Enclose selected expression with math symbol

• Select an expression and press "$" key will automatically enclose the expression with the math symbols.

7. Auto Fraction - Type "/" instead of \frac{}{}.

• Type $e/2$ followed by a "space" key will automatically replace the expression with $\frac{e}{2}$.

• Tip 1: Enclose your fraction expression within round brackets () will help the system identify the boundaries of your fraction.

• Tip 2: Put a space infront of fraction to denote the start of the fraction. Especially useful for series of fractions!

• Tip 3: For longer numerator or denominator expressions (especially when the expressions have white spaces which may trigger the frac-replace prematurely), enclose the expressions in round brackets ().

• Tip 4: The plugin will remove the outermost brackets in numerator and denominator.

8. Shortcut for Align Block

• use "Alt+Shift+A" (Mac: "Option+Shift+A") shortcut key to quickly insert \begin{align*} \end{align*} block

• Tip 1: If you have already typed some expressions and want to add the \begin{align*} and \end{align*} to the front and back, you can first select the texts then press "Alt+Shift+A" (Mac: "Option+Shift+A").

• Tip 2: Quick next line syntax within align block

  • pressing "enter" within an align block will automatically insert \\ to the end of the line, go to next line and add the "&" symbol.
  • press "shift+enter" to go to next line without adding these symbols.

• Tip 3: Changing parameter

  • the default parameter "align*" can be changed in the plugin settings.

• Tip 4: Edit Short Cut

  • You may edit the shortcut keys in Settings -> Hotkeys

9. Shortcut for Matrix Block

• use "Alt+Shift+M" (Mac: "Option+Shift+M") shortcut key to quickly insert \begin{pmatrix} \end{pmatrix} block

• Tip 1: quick next item and next line syntax within matrix block

  • pressing "tab" within a matrix block will automatically insert " & ".
  • pressing "enter" within a matrix block will automatically insert " \\ ".
  • press "shift+enter" to go to next line without adding these symbols.

• Tip 2: Changing parameter

  • the default parameter "pmatrix" can be changed in the plugin settings. e.g. matrix, bmatrix, Bmatrix, vmatrix, Vmatrix

• Tip 3: Edit Short Cut

  • You may edit the shortcut keys in Settings -> Hotkeys

10. Custom shorthand (Now works with multi-letters shorthand!)

• Use multi-letters custom shorthand for common latex strings. e.g. typing "al" followed by "space" key will replace with "\alpha"
• You may set your own custom shorthand in the plugin settings page. Separate the two-letters shorthand and the string with ":" and separate each set of shorthands with ",". e.g. al:\alpha, be:\beta
• Tip: If the expression ends with curly brackets "{}", cursor will automatically be placed within the brackets.
• Note: The system will ignore a shorthand if it is preceeded by an alphabet. eg. "ta" is the shorthand for "\tau. Typing "delta" followed by space will NOT trigger the replacement.
• Below is the list of default shorthand:

Shorthand	String	Shorthand	String	Shorthand	String
sq	\sqrt{}	bb	\mathbb{}	bf	\mathbf{}
te	\text{}	inf	\infty
cd	\cdot	qu	\quad	ti	\times
al	\alpha	be	\beta	ga	\gamma
Ga	\Gamma	de	\delta	De	\Delta
ep	\epsilon	ze	\zeta	et	\eta
th	\theta	Th	\Theta	io	\iota
ka	\kappa	la	\lambda	La	\Lambda
mu	\mu	nu	\nu	xi	\xi
Xi	\Xi	pi	\pi	Pi	\Pi
rh	\rho	si	\sigma	Si	\Sigma
ta	\tau	up	\upsilon	Up	\Upsilon
ph	\phi	Ph	\Phi	ch	\chi
ps	\psi	Ps	\Psi	om	\omega
Om	\Omega

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Note:

• The repo depends on the latest Obsidian API (obsidian.d.ts) in Typescript Definition format, which is still in early alpha so might break anytime!
• This is my first Obsidian Plugin project, bugs might be present. Please use with caution.
• Compatible with builtin vim-mode.

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source code:

see https://github.com/joeyuping/quick_latex_obsidian