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 ag{编号}即可，如：

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

[L(Y,f(X))=(Y-f(X))^2 ag{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

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

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

省略号

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

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

线性方程组

使用case环境将多个公式组合

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

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

另还有gathered环境

$$
left. egin{gathered}
S subseteq T \
S supseteq T
end{gathered} 
ight}
implies S = T  
$$

[left. egin{gathered} A subseteq B \ A supseteq B end{gathered} ight} implies A = B ]

数学模式重音符

$$
hat{a} check{a} 	ilde{a} acute{a}
grave{a} dot{a} ddot{a} reve{a}
ar{a} vec{a} widehat{a} widetilde{a}
$$

[hat{a} check{a} ilde{a} acute{a}\ grave{a} dot{a} ddot{a} reve{a}\ ar{a} vec{a} widehat{a} widetilde{a} ]

矩阵

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

ight]
$$

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

希腊字母

见下表

代码	大写	代码	小写
A	A	alpha	α
B	B	eta	β
Gamma	Γ	gamma	γ
Delta	Δ	delta	δ
E	E	epsilon	ϵ
Z	Z	zeta	ζ
H	H	eta	η
Theta	Θ	heta	θ
I	I	iota	ι
K	K	kappa	κ
Lambda	Λ	lambda	λ
M	M	mu	μ
N	N	u	ν
Xi	Ξ	xi	ξ
O	O	omicron	ο
Pi	Π	pi	π
P	P	ho	ρ
Sigma	Σ	sigma	σ
T	T	au	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} extrm{C}	(_{a}^{b} extrm{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)
igcap A	(igcap A)
igcap_{a}^{b}C	(igcap_{a}^{b}C)
igcup c	(igcup c)
igcup_{a}^{b}C	(igcup_{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 ight ]	(left [ a ight ])
left ( a ight )	(left ( a ight ))
left { a ight }	(left { a ight })
left langle a ight angle	(left langle a ight angle)
left lfloor a ight floor	(left lfloor a ight floor)
left lceil a ight ceil	(left lceil a ight ceil)
supseteqq A	(supseteqq A)

二元关系符

[egin{array} & < & exttt{"<"} & > & exttt{">"} &= & exttt{"="}\ leq & exttt{"leq or le"} & geq & exttt{"geq or ge"} &equiv & exttt{"equiv"}\ ll & exttt{"ll"} & gg & exttt{"gg"} &doteq & exttt{"doteq"}\ prec & exttt{"prec"} & succ & exttt{"succ"} &sim & exttt{"sim"}\ preceq & exttt{"preceq"} & succeq & exttt{"succeq"} &simeq & exttt{"simeq"}\ subset & exttt{"subset"} & supset & exttt{"supset"} &approx & exttt{"approx"}\ subseteq & exttt{"subseteq"} & supseteq & exttt{"supseteq"} &approxeq & exttt{"approxeq"}\ sqsubset & exttt{"sqsubset"} & sqsupset& exttt{"sqsupset"} &Join & exttt{"Join"}\ sqsubseteq & exttt{"sqsubseteq"} & sqsupseteq& exttt{"sqsupseteq"} &owtie & exttt{"owtie"}\ in & exttt{"in"} & i & exttt{" i or owns"} &propto & exttt{"propto"}\ vdash & exttt{"vdash"} & dashv & exttt{"dashv"} &models & exttt{"models"}\ mid & exttt{"mid"} & parallel & exttt{"parallel"} &perp & exttt{"perp"}\ smile & exttt{"smile"} & frown & exttt{"frown"} &asymp & exttt{"asymp"}\ : & exttt{":"} & otin & exttt{" otin"} & eq & exttt{" eq or e"}\ 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	×	imes
÷	div	|	mid
∤∤	mid	⋅	cdot
∘	circ	∗	ast
⨀	igodot	⨂	igotimes
⨁	igoplus	∅	emptyset
⋁	igvee	⋀	igwedge
⨄	iguplus	⨆	igsqcup
∠	angle	30^∘	30 ^ circ
sin	sin	cos	cos
tan	an	cot	cot
′	prime	∭	iiint
⨌	iiiint	∞	infty
∇	abla	∵	ecause
∴	herefore	∀	forall
∃	exists	≯	ot>
⊄	otsubset	sec	sec
↑	uparrow	↓	downarrow
⇑	Uparrow	⇓	Downarrow
→	ightarrow	←	leftarrow
⇒	Rightarrow	⇐	Leftarrow
⟶	longrightarrow	⟵	longleftarrow
⟹	Longrightarrow	⟸	Longleftarrow
	quad (空格)	#	#
⊥	ot

数学字体

字体表

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

色彩表

[egin{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