Help:Math markup

From Memory Alpha, the free Star Trek reference

MediaWiki uses LaTeX markup to render mathematical formulas. It generates either PNG images or simple HTML markup, depending on user preferences and the complexity of the expression. Alternatively, if you are using an advanced browser like Mozilla or Mozilla Firefox, MediaWiki can generate enhanced HTML or even MathML in most cases.

Math markup goes inside <math> ... </math> tags. Line breaks within these tags are fine, and aren't rendered. They're a good idea to keep the raw markup clear (for instance, a line break after each term or row of a matrix).

Note that PNG images use font sizes and types independent of browser settings. Therefore, in most cases these deviate from what HTML renders (the latter does depend on browser settings). Please avoid using TeX markup as part of a line of regular text, as the formulas don't align properly and the font size, as said, usually does not match. Additionally, the background color of the PNG images cannot be changed by the user.

Following are some selected examples of math markup that can be used in Memory Alpha articles. For more detailed information, see Displaying a formula on Wikipedia.

Contents 1 Special characters 2 Subscripts and superscripts 3 Fractions, matrices and multilines 4 Fonts 5 Parenthesizing big expressions 6 Spacing 7 Forced PNG rendering 8 External links

[edit] Special characters

Feature	Syntax	How it looks rendered
std. functions (good)	\sin x + \ln y +\operatorname{sgn} z
std. functions (wrong)	sin x + ln y + sgn z
Modular arithmetic	s_k \equiv 0 \pmod{m}
Derivatives	\nabla \partial x dx \dot x \ddot y
Sets	\forall \exists \empty \emptyset \varnothing
	\in \ni \not \in \notin \subset \subseteq \supset \supseteq
	\cap \bigcap \cup \bigcup \biguplus \setminus \smallsetminus
Logic	p \land \bar{q} \to p\lor \lnot q
Roots	\sqrt{2}\approx 1.4
	\sqrt[n]{x}
Relations	\sim \simeq \cong \le \ge \equiv \not\equiv \approx \ne
Geometric	\Diamond \Box \triangle \angle \perp \mid \nmid \| 45^\circ
Arrows	\leftarrow \rightarrow \leftrightarrow \longleftarrow \longrightarrow \mapsto \longmapsto \nearrow \searrow \swarrow \nwarrow \uparrow \downarrow \updownarrow
	\Leftarrow \Rightarrow \Leftrightarrow \Longleftarrow \Longrightarrow \Longleftrightarrow \Uparrow \Downarrow \Updownarrow
Special	\oplus \otimes \pm \mp \hbar \dagger \ddagger \star \circ \cdot \times \bullet \infty \ell \mho \Finv \Re \Im \wp \complement \diamondsuit \heartsuit \clubsuit \spadesuit \Game \flat \natural \sharp

[edit] Subscripts and superscripts

Feature	Syntax	How it looks rendered
Superscript	a^2
Subscript	a_2
Grouping	a^{2+2}
	a_{i,j}
Combining sub & super	x_2^3
Derivative (good)	x'
Derivative (wrong in HTML)	x^\prime
Derivative (wrong in PNG)	x\prime
Underlines and overlines	\hat a \bar b \vec c \widehat {d e f} \overline {g h i} \underline {j k l}
Arrows	A \xleftarrow{n+\mu-1} B \xrightarrow[T]{n\pm i-1} C
Overbraces	\overbrace{ 1+2+\cdots+100 }^{5050}
Underbraces	\underbrace{ a+b+\cdots+z }_{26}
Sum	\sum_{k=1}^N k^2
Product	\prod_{i=1}^N x_i
Limit	\lim_{n \to \infty}x_n
Integral	\int_{-N}^{N} e^x\, dx
Line Integral	\oint_{C} x^3\, dx + 4y^2\, dy

[edit] Fractions, matrices and multilines

Feature	Syntax	How it looks rendered
Fractions	\frac{2}{4} or {2 \over 4}
Binomial coefficients	{n \choose k}
Matrices	\begin{pmatrix} x & y \\ z & v \end{pmatrix}
	\begin{bmatrix} 0 & \cdots & 0 \\ \vdots & \ddots & \vdots \\ 0 & \cdots & 0\end{bmatrix}
	\begin{Bmatrix} x & y \\ z & v \end{Bmatrix}
	\begin{vmatrix} x & y \\ z & v \end{vmatrix}
	\begin{Vmatrix} x & y \\ z & v \end{Vmatrix}
	\begin{matrix} x & y \\ z & v \end{matrix}
Case distinctions	f(n) = \left \{ \begin{matrix} n/2, & \mbox{if }n\mbox{ is even} \\ 3n+1, & \mbox{if }n\mbox{ is odd} \end{matrix} \right.
Multiline equations	\begin{matrix}f(n+1) & = & (n+1)^2 \\ \ & = & n^2 + 2n + 1 \end{matrix}

[edit] Fonts

Feature	Syntax	How it looks rendered
Greek letters	\alpha \beta \gamma \Gamma \phi \Phi \Psi\ \tau \Omega
Blackboard bold	x\in\mathbb{R}\sub\mathbb{C}
Boldface (vectors)	\mathbf{x}\cdot\mathbf{y} = 0
Boldface (Greek)	\boldsymbol{\alpha} + \boldsymbol{\beta} + \boldsymbol{\gamma}
Fraktur typeface	\mathfrak{a} \mathfrak{B}
Script	\mathcal{ABC}
Hebrew	\aleph \beth \gimel \daleth
Non-italicized characters	\mbox{abc}
Mixed italics (bad)	\mbox{if} n \mbox{is even}
Mixed italics (good)	\mbox{if }n\mbox{ is even}

[edit] Parenthesizing big expressions

Feature	Syntax	How it looks rendered
Not good	( \frac{1}{2} )
Better	\left ( \frac{1}{2} \right )

You can use various delimiters with \left and \right:

Feature	Syntax	How it looks rendered
Parentheses	\left ( A \right )
Brackets	\left [ A \right ]
Braces	\left \{ A \right \}
Angle brackets	\left \langle A \right \rangle
Bars and double bars	\left | A \right | and \left \| B \right \|
Delimiters can be mixed, as long as \left and \right match	\left [ 0,1 \right ) \left \langle \psi \right |
Use \left. and \right. if you don't want a delimiter to appear	\left . \frac{A}{B} \right \} \to X

[edit] Spacing

Note that TeX handles most spacing automatically, but you may sometimes want manual control.

Feature	Syntax	How it looks rendered
double quad space	a \qquad b
quad space	a \quad b
text space	a\ b
large space	a\;b
medium space	a\>b	[not supported]
small space	a\,b
no space	ab
negative space	a\!b

[edit] Forced PNG rendering

If you must, it is possible to force the formula to render as PNG, without affecting the display of the formula, by adding \,\! (small space and negative space, which cancel out) somewhere inside the math tags (probably at the end).

This could be useful to keep the rendering of formulas in a proof consistent, for example, or to fix formulas that render incorrectly in HTML (x prime, or a^{2+2}), or to demonstrate how something is rendered when it would normally show up as HTML (as in the examples above). For instance:

Syntax	How it looks rendered
a^{2+2}
a^{2+2} \,\!
\int_{-N}^{N} e^x\, dx
\int_{-N}^{N} e^x\, dx \,\!

This has been tested with most of the formulas on this page, and seems to work perfectly.

You might want to include a comment in the HTML so people don't "correct" the formula by removing it:

<!-- The \,\! is to keep the formula rendered as PNG instead of HTML. Please don't remove it.-->

[edit] External links

• LaTeX at Wikipedia
• Getting Started with LaTeX at The University of Dublin Trinity College School of Mathematics - a LaTeX tutorial
• A Gentle Introduction to TeX at The Comprehensive TeX Archive Network - a PDF document introducing TeX; see page 39 onwards for a good introduction to the math side of things
• The Comprehensive LaTeX Symbol List at CTAN - a complete list of symbols available in LaTeX
• TeX reference card at Florida State University School of Computational Science - a TeX quick reference card