编辑你的数学公式——markdown中latex的使用

前言

最近开始使用起markdown来记学习笔记，因为经常有公式要写，就需要用到latex，到网上查来查去又不太方便，而且也很少能查到写的比较全的，就准备写下这篇文章。

插入数学公式

在markdown中插入数学公式的语法有两种：

1. 行内公式$数学公式$
2. 行间公式$$数学公式$$

如：

函数$ L(Y,f(X))=(Y-f(X))^2 $
函数
$$
L(Y,f(X))=(Y-f(X))^2
$$

函数$ L(Y,f(X))=(Y-f(X))^2 ​$

函数

\[L(Y,f(X))=(Y-f(X))^2
\]

如果需要加编号，加上\tag{编号}即可，如：

$$
L(Y,f(X))=(Y-f(X))^2
\tag{1}
$$

\[L(Y,f(X))=(Y-f(X))^2
\tag{1}
\]

上下标

上标可由^表示，下标可由_表示，若上下标不止一个字符则需用花括号{}括起

如：

n_x n^x

\(n_x\) \(n^x\)

分数

分数输入格式为\frac{分子}{分母}

如：

$\frac{1}{N}$

\(\frac{1}{N}\)

括号

() [] 和|都表示自己，但是{}需加\

如：

$() [] | \{\}$

\(() [] | \{\}\)

上下划线

$$
\begin{array}
\overline{a+b} \\
\underline{a+b} \\
\overleftarrow{a+b} \\
\underleftarrow{a+b} \\
\underleftrightarrow{a+b} \\
\vec x = \vec{AB} \\
\overbrace {a+b}^\text{a,b} \\
a+\rlap{\overbrace{\phantom{b+c+d}}^m}b+\underbrace{c+d+e}_n+f
\end{array}
$$

\[\begin{array}
\overline{a+b} \\
\underline{a+b} \\
\overleftarrow{a+b} \\
\underleftarrow{a+b} \\
\underleftrightarrow{a+b} \\
\vec x = \vec{AB} \\
\overbrace {a+b}^\text{a,b} \\
a+\rlap{\overbrace{\phantom{b+c+d}}^m}b+\underbrace{c+d+e}_n+f
\end{array}
\]

省略号

$$
\begin{eqnarray*} \\
\ldots \\
\cdots \\
\vdots \\
\ddots \\
\end{eqnarray*}
$$

\[\begin{eqnarray*} \\
\ldots \\
\cdots \\
\vdots \\
\ddots \\
\end{eqnarray*}
\]

线性方程组

使用case环境将多个公式组合

$$
L(Y,f(X))=
\begin{cases}
1,\quad &Y\neq f(X)\\
0,\quad &Y=f(X)
\end{cases}
$$

\[L(Y,f(X))=
\begin{cases}
1,\quad &Y\neq f(X)\\
0,\quad &Y=f(X)
\end{cases}
\]

另还有gathered环境

$$
\left. \begin{gathered}
S \subseteq T \\
S \supseteq T
\end{gathered} \right\}
\implies S = T
$$

\[\left. \begin{gathered}
A \subseteq B \\
A \supseteq B
\end{gathered} \right\}
\implies A = B
\]

数学模式重音符

$$
\hat{a} \check{a} \tilde{a} \acute{a}
\grave{a} \dot{a} \ddot{a} \breve{a}
\bar{a} \vec{a} \widehat{a} \widetilde{a}
$$

\[\hat{a} \check{a} \tilde{a} \acute{a}\\
\grave{a} \dot{a} \ddot{a} \breve{a}\\
\bar{a} \vec{a} \widehat{a} \widetilde{a}
\]

矩阵

$$
X =
\left[
\begin{matrix}
 x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
 x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
 x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
\end{matrix}
\right]
$$

\[X =
\left[
\begin{matrix}
x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
x^{(1)} & x^{(2)} & \cdots & x^{(m)} \\
\end{matrix}
\right]
\]

希腊字母

见下表

代码	大写	代码	小写
A	A	\alpha	α
B	B	\beta	β
\Gamma	Γ	\gamma	γ
\Delta	Δ	\delta	δ
E	E	\epsilon	ϵ
Z	Z	\zeta	ζ
H	H	\eta	η
\Theta	Θ	\theta	θ
I	I	\iota	ι
K	K	\kappa	κ
\Lambda	Λ	\lambda	λ
M	M	\mu	μ
N	N	\nu	ν
\Xi	Ξ	\xi	ξ
O	O	\omicron	ο
\Pi	Π	\pi	π
P	P	\rho	ρ
\Sigma	Σ	\sigma	σ
T	T	\tau	τ
\Upsilon	Υ	\upsilon	υ
\Phi	Φ	\phi	ϕ
X	X	\chi	χ
\Psi	Ψ	\psi	ψ
\Omega	Ω	\omega	ω

常用数学符号

包括积分符号、集合符号、累乘累加符号等

见下表：

转义符号	效果
\log_{x}y = \arccos z	\(\log_{x}y = \arccos z\)
\frac{a} {b}	\(\frac{a} {b}\)
_{a}^{b}\textrm{C}	\(_{a}^{b}\textrm{C}\)
\frac{\partial {z_x}}{\partial x}	\(\frac{\partial {z_x}}{\partial x}\)
\frac{\partial^2 {x}}{\partial x^2}	\(\frac{\partial^2 {x}}{\partial x^2}\)
\frac{\mathrm{d} y}{\mathrm{d} x}	\(\frac{\mathrm{d} y}{\mathrm{d} x}\)
\int x	\(\int x\)
\int_{a}^{b}x	\(\int_{a}^{b}x\)
\oint a	\(\oint a\)
\oint_{a}^{b}C	\(\oint_{a}^{b}C\)
\iint_{a}^{v}C	\(\iint_{a}^{v}C\)
\bigcap A	\(\bigcap A\)
\bigcap_{a}^{b}C	\(\bigcap_{a}^{b}C\)
\bigcup c	\(\bigcup c\)
\bigcup_{a}^{b}C	\(\bigcup_{a}^{b}C\)
\lim_{c}X	\(\lim_{c}X\)
\sum a	\(\sum a\)
\sum_{a}^{b}C	\(\sum_{a}^{b}C\)
\sqrt{X}	\(\sqrt{X}\)
\sqrt[a]{X}	\(\sqrt[a]{X}\)
\prod X	\(\prod X\)
\prod_{a}^{b} X	\(\prod_{a}^{b} X\)
\coprod X	\(\coprod X\)
\coprod_{a}^{b} X	\(\coprod_{a}^{b} X\)
\left [ a \right ]	\(\left [ a \right ]\)
\left ( a\right )	\(\left ( a\right )\)
\left \{ a \right \}	\(\left \{ a \right \}\)
\left \langle a \right \rangle	\(\left \langle a \right \rangle\)
\left \lfloor a \right \rfloor	\(\left \lfloor a \right \rfloor\)
\left \lceil a \right \rceil	\(\left \lceil a \right \rceil\)
\supseteqq A	\(\supseteqq A\)

二元关系符

\[\begin{array}
& < &\texttt{"<"} & > &\texttt{">"} &= &\texttt{"="}\\
\leq &\texttt{"\leq or \le"} & \geq &\texttt{"\geq or \ge"} &\equiv &\texttt{"\equiv"}\\
\ll &\texttt{"\ll"} & \gg &\texttt{"\gg"} &\doteq &\texttt{"\doteq"}\\
\prec &\texttt{"\prec"} & \succ &\texttt{"\succ"} &\sim &\texttt{"\sim"}\\
\preceq &\texttt{"\preceq"} & \succeq &\texttt{"\succeq"} &\simeq &\texttt{"\simeq"}\\
\subset &\texttt{"\subset"} & \supset &\texttt{"\supset"} &\approx &\texttt{"\approx"}\\
\subseteq &\texttt{"\subseteq"} & \supseteq &\texttt{"\supseteq"} &\approxeq &\texttt{"\approxeq"}\\
\sqsubset &\texttt{"\sqsubset"} & \sqsupset&\texttt{"\sqsupset"} &\Join &\texttt{"\Join"}\\
\sqsubseteq &\texttt{"\sqsubseteq"} & \sqsupseteq&\texttt{"\sqsupseteq"} &\bowtie &\texttt{"\bowtie"}\\
\in &\texttt{"\in"} & \ni &\texttt{"\ni or \owns"} &\propto &\texttt{"\propto"}\\
\vdash &\texttt{"\vdash"} & \dashv &\texttt{"\dashv"} &\models &\texttt{"\models"}\\
\mid &\texttt{"\mid"} & \parallel &\texttt{"\parallel"} &\perp &\texttt{"\perp"}\\
\smile &\texttt{"\smile"} & \frown &\texttt{"\frown"} &\asymp &\texttt{"\asymp"}\\
: &\texttt{":"} & \notin &\texttt{"\notin"} &\neq &\texttt{"\neq or \ne"}\\
\end{array}
\]

三角函数与逻辑数学字符

数学字符	输入	数学字符	输入
±	\pm	×	\times
÷	\div	|	\mid
∤∤	\nmid	⋅	\cdot
∘	\circ	∗	\ast
⨀	\bigodot	⨂	\bigotimes
⨁	\bigoplus	∅	\emptyset
⋁	\bigvee	⋀	\bigwedge
⨄	\biguplus	⨆	\bigsqcup
∠	\angle	30^∘	30 ^ \circ
sin	\sin	cos	\cos
tan	\tan	cot	\cot
′	\prime	∭	\iiint
⨌	\iiiint	∞	\infty
∇	\nabla	∵	\because
∴	\therefore	∀	\forall
∃	\exists	≯	\not>
⊄	\not\subset	sec	\sec
↑	\uparrow	↓	\downarrow
⇑	\Uparrow	⇓	\Downarrow
→	\rightarrow	←	\leftarrow
⇒	\Rightarrow	⇐	\Leftarrow
⟶	\longrightarrow	⟵	\longleftarrow
⟹	\Longrightarrow	⟸	\Longleftarrow
	\quad (空格)	#	#
⊥	\bot

数学字体

字体表

\[\begin{array}
\texttt{"normal"} &\texttt{} & ABCDEFGHIJKLMNOPQRSTUVWXYZ\\
\texttt{"blackboard"} &\texttt{\mathbb} &\mathbb{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"boldface"} &\texttt{\mathbf} &\mathbf{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"typewriter"} &\texttt{\mathtt} &\mathtt{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"roman"} &\texttt{\mathrm} &\mathrm{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"sans-serif"} &\texttt{\mathsf} &\mathsf{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"calligraphic"}&\texttt{\mathcal} &\mathcal{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"script"} &\texttt{\mathscr} &\mathscr{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\texttt{"fraktur"} &\texttt{\mathfrak}&\mathfrak{ABCDEFGHIJKLMNOPQRSTUVWXYZ}\\
\end{array}
\]

色彩表

\[\begin{array}
\hline
\verb+\color{black}{黑色}+ & \color{black}{黑色} \\
\verb+\color{darkgray}{深灰}+ & \color{darkgray}{深灰}\\
\verb+\color{gray}{灰色}+ & \color{gray}{灰色} \\
\verb+\color{silver}{银色}+ & \color{silver}{银色} \\
\verb+\color{lightgray}{浅灰}+&\color{lightgray}{浅灰}\\
\verb+\color{white}{白色}+ & \color{white}{白色} \\
\hline
\verb+\color{brown}{棕色}+ & \color{brown}{棕色} \\
\verb+\color{maroon}{栗色}+ & \color{maroon}{栗色} \\
\verb+\color{red}{红色}+ & \color{red}{红色} \\
\verb+\color{fuchsia}{桃红}+ & \color{fuchsia}{桃红} \\
\verb+\color{magenta}{品红}+ & \color{magenta}{品红} \\
\verb+\color{pink}{粉红}+ & \color{pink}{粉红} \\
\verb+\color{orange}{橙色}+ & \color{orange}{橙色} \\
\verb+\color{yellow}{黄色}+ & \color{yellow}{黄色} \\
\verb+\color{lime}{青柠}+ & \color{lime}{青柠} \\
\verb+\color{olive}{橄榄}+ & \color{olive}{橄榄} \\
\verb+\color{green}{绿色}+ & \color{green}{绿色} \\
\verb+\color{aqua}{水绿}+ & \color{aqua}{水绿} \\
\verb+\color{cyan}{青色}+ & \color{cyan}{青色} \\
\verb+\color{teal}{靛青}+ & \color{teal}{靛青} \\
\verb+\color{blue}{蓝色}+ & \color{blue}{蓝色} \\
\verb+\color{navy}{海蓝}+ & \color{navy}{海蓝} \\
\verb+\color{violet}{罗兰}+ & \color{purple}{罗兰} \\
\verb+\color{purple}{紫色}+ & \color{purple}{紫色} \\
\hline
\end{array}参考
\]

参考：

https://www.cnblogs.com/nowgood/p/Latexstart.html

http://jzqt.github.io/2015/06/30/Markdown中写数学公式/

https://blog.csdn.net/u014630987/article/details/70156489

https://blog.csdn.net/cclethe/article/details/79022216