0. hat
$abc\hat def$
![](https://images2018.cnblogs.com/blog/625108/201808/625108-20180827211814650-2104025648.png) $ab\widehat{cde}f$
1. 箭头上的文字
$\underrightarrow{\text{你的文字}}$
($A \xleftarrow{n=0} B \xrightarrow[T]{n>0} C$
)
定义:≜(\triangleq
)
2. 特殊的箭头
3. 下标
4. 在符号底部写符号:\underset
\underset{0\leq j \leq k-1}{\arg\min}
A 在 B 下
\underset{A}{B}
5. 在符号下部换行:\understack
\sum_{\substack{0<i<n \\ 0<j<n}} A_{ij}
6. Latex 符号总结(各种箭头符号)
latex
显示效果
\uparrow
↑↑
\downarrow
↓↓
\Uparrow
⇑⇑
\Downarrow
⇓⇓
\updownarrow
↕↕
\Updownarrow
⇕⇕
\rightarrow
→→
\leftarrow
←←
\Rightarrow
⇒⇒
\Leftarrow
⇐⇐
\leftrightarrow
↔↔
\Leftrightarrow
⇔⇔
\longrightarrow
⟶⟶
\longleftarrow
⟵⟵
\Longrightarrow
⟹⟹
\Longleftarrow
⟸⟸
\longleftrightarrow
⟷⟷
\Longleftrightarrow
⟺
latex
显示效果
\mapsto
↦↦
\longmapsto
⟼⟼
\hookleftarrow
↩↩
\hookrightarrow
↪↪
\leftharpoonup
↼↼
\rightharpoonup
⇀⇀
\leftharpoondown
↽↽
\rightharpoondown
⇁⇁
\rightleftharpoons
⇌⇌
\leadsto
⇝⇝
\nearrow
↗↗
\searrow
↘↘
\swarrow
↙↙
\nwarrow
↖↖
\nleftarrow
↚↚
\nrightarrow
↛↛
\nLeftarrow
⇍⇍
\nRightarrow
⇏⇏
\nleftrightarrow
↮↮
\nLeftrightarrow
⇎⇎
\dashrightarrow
⇢⇢
\dashleftarrow
⇠⇠
\leftleftarrows
⇇⇇
\leftrightarrows
⇆⇆
\Lleftarrow
⇚⇚
\twoheadleftarrow
↞↞
\leftarrowtail
↢↢
\looparrowleft
↫↫
\leftrightharpoons
⇋⇋
\curvearrowleft
↶↶
\circlearrowleft
↺↺
\Lsh
↰↰
\upuparrows
⇈⇈
\upharpoonleft
↿↿
\downharpoonleft
⇃⇃
\multimap
⊸⊸
\leftrightsquigarrow
↭↭
\rightrightarrows
⇉⇉
\rightleftarrows
⇄⇄
\rightrightarrows
⇉⇉
\rightleftarrows
⇄⇄
\twoheadrightarrow
↠↠
\rightarrowtail
↣↣
\looparrowright
↬↬
\rightleftharpoons
⇌⇌
\curvearrowright
↷↷
\circlearrowright
↻↻
\Rsh
↱↱
\downdownarrows
⇊⇊
\upharpoonright
↾↾
\downharpoonright
⇂⇂
\rightsquigarrow
⇝