【转载】【latex】latex公式编辑概述

时间:2022-08-16 06:10:23

源链接:http://blog.sciencenet.cn/home.php?mod=space&uid=2043&do=blog&id=244080

                http://hepg.sdu.edu.cn/Service/tips/latex/doc2/Calculus.html

常用特殊符号链接:http://hepg.sdu.edu.cn/Service/tips/latex/doc2/MathSymb.html

 

LaTeX 最强大的功能就是显示美丽的数学公式, 下面我们来看这些公式是怎么实现的.

1、数学公式的前后要加上$或/(和/),比如:$f(x) = 3x + 7$和/(f(x) = 3x + 7/)效果是一样的;
如果用/[和/],或者使用$$和$$,则改公式独占一行;
如果用/begin{equation}和/end{equation},则公式除了独占一行还会自动被添加序号. 如何公式不想编号则使用/begin{equation*}和/end{equation*}.

2、字符
普通字符在数学公式中含义一样,除了
# $ % & ~ _ ^ / { }
若要在数学环境中表示这些符号# $ % & _ { }, 需要分别表示为/# /$ /% /& /_ /{ /},即在个字符前加上/。

3、上标和下标
用^来表示上标,用_来表示下标. 看一简单例子:

$$/sum_{i=1}^n a_i=0$$
$$f(x)=x^{x^x}$$

效果:

【转载】【latex】latex公式编辑概述

这里有更多的 LaTeX上标下标的设置.

4、希腊字母

【转载】【latex】latex公式编辑概述

更多请参见 这里

 

5、数学函数 【转载】【latex】latex公式编辑概述

6、在公式中插入文本
可以通过/mbox{text}在公式中添加text,比如:

/documentclass{article}
/usepackage{CJK}
/begin{CJK*}{GBK}{song}
/begin{document}
$$/mbox{对任意的$x>0$}, /mbox{有 }f(x)>0. $$
/end{CJK*}
/end{document}

效果:

【转载】【latex】latex公式编辑概述

7、分数及开方
/frac{ numerator }{ denominator }
/sqrt{ expression }表示开平方, /sqrt[n]{ expression }表示开n次方。

8、省略号(3个点)
/ldots表示跟文本底线对齐的省略号;/cdots表示跟文本中线对齐的省略号,

比如:
【转载】【latex】latex公式编辑概述

表示为
$$f(x_1,x_x,/ldots,x_n) = x_1^2 + x_2^2 + /cdots + x_n^2 $$

9、括号和分隔符
()和[ ]和|对应于自己;{}对应于/{ /}; ||对应于/|。
当要显示大号的括号或分隔符时,要对应用/left和/right,如:

/[ f(x,y,z) = 3y^2 z /left( 3 + /frac{7x+5}{1 + y^2} /right)./]

对应于

【转载】【latex】latex公式编辑概述

/left. /right. 只用与匹配,本身是不显示的,比如,要输出:

【转载】【latex】latex公式编辑概述
则用
$$/left. /frac{du}{dx} /right|_{x=0}.$$

10、多行的数学公式

【转载】【latex】latex公式编辑概述
可以表示为:
/begin{eqnarray*}
/cos 2/theta & = & /cos^2 /theta - /sin^2 /theta //
& = & 2 /cos^2 /theta - 1.
/end{eqnarray*}

 

其中&是对其点,表示在此对齐。
*使latex不自动显示序号,如果想让latex自动标上序号,则把*去掉

11、矩阵
【转载】【latex】latex公式编辑概述
表示为:
The /emph{characteristic polynomial} $/chi(/lambda)$ of the
$3 /times 3$~matrix
/[ /left( /begin{array}{ccc}
a & b & c //
d & e & f //
g & h & i /end{array} /right)/]
is given by the formula
/[ /chi(/lambda) = /left| /begin{array}{ccc}
/lambda - a & -b & -c //
-d & /lambda - e & -f //
-g & -h & /lambda - i /end{array} /right|./]

c表示向中对齐,l表示向左对齐,r表示向右对齐。

12、 导数、极限、求和、积分

The expressions

【转载】【latex】latex公式编辑概述

are obtained in LaTeX by typing /frac{du}{dt} and /frac{d^2 u}{dx^2} respectively. The mathematical symbol 【转载】【latex】latex公式编辑概述 is produced using /partial . Thus the Heat Equation

【转载】【latex】latex公式编辑概述

is obtained in LaTeX by typing

/[ /frac{/partial u}{/partial t}
= h^2 /left( /frac{/partial^2 u}{/partial x^2}
+ /frac{/partial^2 u}{/partial y^2}
+ /frac{/partial^2 u}{/partial z^2} /right) /]

To obtain mathematical expressions such as

【转载】【latex】latex公式编辑概述

in displayed equations we type /lim_{x /to +/infty} , /inf_{x > s} and /sup_K respectively. Thus to obtain

【转载】【latex】latex公式编辑概述

(in LaTeX) we type

/[ /lim_{x /to 0} /frac{3x^2 +7x^3}{x^2 +5x^4} = 3./] 

To obtain a summation sign such as

【转载】【latex】latex公式编辑概述

we type /sum_{i=1}^{2n} . Thus

【转载】【latex】latex公式编辑概述

is obtained by typing

/[ /sum_{k=1}^n k^2 = /frac{1}{2} n (n+1)./] 

We now discuss how to obtain integrals in mathematical documents. A typical integral is the following:

【转载】【latex】latex公式编辑概述

This is typeset using

/[ /int_a^b f(x)/,dx./] 

The integral sign 【转载】【latex】latex公式编辑概述 is typeset using the control sequence /int , and the limits of integration (in this case a and b are treated as a subscript and a superscript on the integral sign.

Most integrals occurring in mathematical documents begin with an integral sign and contain one or more instances of d followed by another (Latin or Greek) letter, as in dx , dy and dt . To obtain the correct appearance one should put extra space before the d , using /, . Thus

【转载】【latex】latex公式编辑概述
【转载】【latex】latex公式编辑概述
【转载】【latex】latex公式编辑概述

and

【转载】【latex】latex公式编辑概述

are obtained by typing

/[ /int_0^{+/infty} x^n e^{-x} /,dx = n!./] 
/[ /int /cos /theta /,d/theta = /sin /theta./] 
/[ /int_{x^2 + y^2 /leq R^2} f(x,y)/,dx/,dy
= /int_{/theta=0}^{2/pi} /int_{r=0}^R
f(r/cos/theta,r/sin/theta) r/,dr/,d/theta./]

and

/[ /int_0^R /frac{2x/,dx}{1+x^2} = /log(1+R^2)./] 

respectively.

In some multiple integrals (i.e., integrals containing more than one integral sign) one finds that LaTeX puts too much space between the integral signs. The way to improve the appearance of of the integral is to use the control sequence /! to remove a thin strip of unwanted space. Thus, for example, the multiple integral

【转载】【latex】latex公式编辑概述

is obtained by typing

/[ /int_0^1 /! /int_0^1 x^2 y^2/,dx/,dy./] 

Had we typed

/[ /int_0^1 /int_0^1 x^2 y^2/,dx/,dy./] 

we would have obtained

【转载】【latex】latex公式编辑概述

A particularly noteworthy example comes when we are typesetting a multiple integral such as

【转载】【latex】latex公式编辑概述

Here we use /! three times to obtain suitable spacing between the integral signs. We typeset this integral using

/[ /int /!/!/! /int_D f(x,y)/,dx/,dy./] 

Had we typed

/[ /int /int_D f(x,y)/,dx/,dy./] 

we would have obtained

【转载】【latex】latex公式编辑概述

The following (reasonably complicated) passage exhibits a number of the features which we have been discussing:

【转载】【latex】latex公式编辑概述

One would typeset this in LaTeX by typing

In non-relativistic wave mechanics, the wave function

$/psi(/mathbf{r},t)$ of a particle satisfies the

/emph{Schr/"{o}dinger Wave Equation}

/[ i/hbar/frac{/partial /psi}{/partial t}

= /frac{-/hbar^2}{2m} /left(

/frac{/partial^2}{/partial x^2}

+ /frac{/partial^2}{/partial y^2}

+ /frac{/partial^2}{/partial z^2}

/right) /psi + V /psi./]

It is customary to normalize the wave equation by

demanding that

/[ /int /!/!/! /int /!/!/! /int_{/textbf{R}^3}

/left| /psi(/mathbf{r},0) /right|^2/,dx/,dy/,dz = 1./]

A simple calculation using the Schr/"{o}dinger wave

equation shows that

/[ /frac{d}{dt} /int /!/!/! /int /!/!/! /int_{/textbf{R}^3}

/left| /psi(/mathbf{r},t) /right|^2/,dx/,dy/,dz = 0,/]

and hence

/[ /int /!/!/! /int /!/!/! /int_{/textbf{R}^3}

/left| /psi(/mathbf{r},t) /right|^2/,dx/,dy/,dz = 1/]

for all times~$t$. If we normalize the wave function in this

way then, for any (measurable) subset~$V$ of $/textbf{R}^3$

and time~$t$,

/[ /int /!/!/! /int /!/!/! /int_V

/left| /psi(/mathbf{r},t) /right|^2/,dx/,dy/,dz/]

represents the probability that the particle is to be found

within the region~$V$ at time~$t$.


特殊符号输入:

Mathematical Symbols

There are numerous mathematical symbols that can be used in mathematics mode. These are obtained by typing an appropriate control sequence.

Miscellaneous Symbols:
【转载】【latex】latex公式编辑概述
``Large'' Operators:
【转载】【latex】latex公式编辑概述
Binary Operations:
【转载】【latex】latex公式编辑概述
Relations:
【转载】【latex】latex公式编辑概述
Negated Relations:
【转载】【latex】latex公式编辑概述
Arrows:
【转载】【latex】latex公式编辑概述
Openings:
【转载】【latex】latex公式编辑概述
Closings:
【转载】【latex】latex公式编辑概述
Alternative Names: 【转载】【latex】latex公式编辑概述