c*****t
发帖数: 520 | 1 Perhaps it is a foolish question.
I think that some types of Schrodinger equations and reaction-diffusion
equations are similar.
Semilinear Schrodinger equation: iu_t=u_xx+f(u).
Semilinear reaction-diffusion equation: u_t=u_xx+f(u).
But the methods for them are quite different. For example, for reaction-
diffusion equations, people ofen study the long time behavior of the
solutions by constructing subsolutions and/or supersolutions and using
comparison principle. For Schrodinger equations, perh... 阅读全帖 |
|
V*P
发帖数: 155 | 2 【 以下文字转载自 Statistics 讨论区 】
发信人: VlP (VlP), 信区: Statistics
标 题: Excel 能否写个 equation with an independent variable
发信站: BBS 未名空间站 (Thu Sep 5 07:05:24 2013, 美东)
比如我有： A1=2, A2=x, A3=6, A1*A2=A6
正常情况下，我可以用 A3/A1 来得到 x 的值，但是我想用一种像calculator那种的输
入求解，类似这样的 f ( x, A1 * x = A3 ) . An equation A1 * x = A3 with
independent variable x, and solve for x.
我需要在excel 的一个 cell输入x的值（A1和A3是随时需要变化的，所以x的值也会随
着变化），我不是不想用 A3/A1 这样的formula ，而是因为formula太太复杂，如果我
写一个equation，再求求x的formula,很容易出现 algebra mistake，太长太复杂的
equat... 阅读全帖 |
|
s*******l
发帖数: 60 | 3 With powerpoint 2007, the equations can't be displayed automatically. Is
there a solution to solve this issue?
FYI, I attached a .pptx file with three equations. I can make the equations
to display via a very inconvenient way. There should be someway to set up
Powerpoint 2007 to display equations automatically. Please advise.
Thanks.
Update:
Actually, as I opened .pptx file with many equations from E-mail, all of
equations was disappeared in powerpoint 2007. Neither these equations can be
automa |
|
V*P
发帖数: 155 | 4 【 以下文字转载自 Statistics 讨论区 】
发信人: VlP (VlP), 信区: Statistics
标 题: Excel 能否写个 equation with an independent variable
发信站: BBS 未名空间站 (Thu Sep 5 07:05:24 2013, 美东)
比如我有： A1=2, A2=x, A3=6, A1*A2=A6
正常情况下，我可以用 A3/A1 来得到 x 的值，但是我想用一种像calculator那种的输
入求解，类似这样的 f ( x, A1 * x = A3 ) . An equation A1 * x = A3 with
independent variable x, and solve for x.
我需要在excel 的一个 cell输入x的值（A1和A3是随时需要变化的，所以x的值也会随
着变化），我不是不想用 A3/A1 这样的formula ，而是因为formula太太复杂，如果我
写一个equation，再求求x的formula,很容易出现 algebra mistake，太长太复杂的
equat... 阅读全帖 |
|
V*P
发帖数: 155 | 5 【 以下文字转载自 Statistics 讨论区 】
发信人: VlP (VlP), 信区: Statistics
标 题: Excel 能否写个 equation with an independent variable
发信站: BBS 未名空间站 (Thu Sep 5 07:05:24 2013, 美东)
比如我有： A1=2, A2=x, A3=6, A1*A2=A6
正常情况下，我可以用 A3/A1 来得到 x 的值，但是我想用一种像calculator那种的输
入求解，类似这样的 f ( x, A1 * x = A3 ) . An equation A1 * x = A3 with
independent variable x, and solve for x.
我需要在excel 的一个 cell输入x的值（A1和A3是随时需要变化的，所以x的值也会随
着变化），我不是不想用 A3/A1 这样的formula ，而是因为formula太太复杂，如果我
写一个equation，再求求x的formula,很容易出现 algebra mistake，太长太复杂的
equat... 阅读全帖 |
|
i****d
发帖数: 255 | 6 I would like to assign a single number for a couple of equations/
inequalities which
belong to the same problem, like
a+b = c
d+e = f (1)
g+h < i
This can be done if the number of equations is odd as I can put the number
after
the equation in the middle. What about if I have 4 or 6 equations? Any there
any other general ways for this?
I tried subequations also, but it does't align the equations.
Thank you for time! |
|
B*B
发帖数: 87 | 7 一个麦克斯韦方程解的存在性和唯一性的问题。
需要证明三维空间里面partial differential equations形式的Maxwell equations的
解的existence and uniqueness。给定初始条件initial condition,对t=0时的E和H的
值作为initial condition。求解t为任意时刻的E和H的值。
然后这是一个Cauchy problem of Maxwell equations。
我不求解Boundary condition问题，只是求解Cauchy问题。
要证明这个existence和uniqueness需要怎么做？
我看了一些PDE的书，都是介绍用Cauchy－Kowalevski theorem或者Holmgren theorem。
但是怎么应用这定理完全没有溉念。
因为看到PDE书基本上都是介绍通用的PDE，没有专门对maxwell equations的。
求教这个证明的思路，感觉对PDE的人来说应该不困难。
但是就是找不到相关的文献或者书本具体针对maxwell equations 讨论的。
真心求高人指教。 |
|
B*B
发帖数: 87 | 8 一个麦克斯韦方程解的存在性和唯一性的问题。
需要证明三维空间里面partial differential equations形式的Maxwell equations的
解的existence and uniqueness。给定初始条件initial condition,对t=0时的E和H的
值作为initial condition。求解t为任意时刻的E和H的值。
然后这是一个Cauchy problem of Maxwell equations。
我不求解Boundary condition问题，只是求解Cauchy问题。
要证明这个existence和uniqueness需要怎么做？
我看了一些PDE的书，都是介绍用Cauchy－Kowalevski theorem或者Holmgren theorem。
但是怎么应用这定理完全没有溉念。
因为看到PDE书基本上都是介绍通用的PDE，没有专门对maxwell equations的。
求教这个证明的思路，感觉对PDE的人来说应该不困难。
但是就是找不到相关的文献或者书本具体针对maxwell equations 讨论的。
真心求高人指教。 |
|
B*B
发帖数: 87 | 9 一个麦克斯韦方程解的存在性和唯一性的问题。
需要证明三维空间里面partial differential equations形式的Maxwell equations的
解的existence and uniqueness。给定初始条件initial condition,对t=0时的E和H的
值作为initial condition。求解t为任意时刻的E和H的值。
然后这是一个Cauchy problem of Maxwell equations。
我不求解Boundary condition问题，只是求解Cauchy问题。
要证明这个existence和uniqueness需要怎么做？
我看了一些PDE的书，都是介绍用Cauchy－Kowalevski theorem或者Holmgren theorem。
但是怎么应用这定理完全没有溉念。
因为看到PDE书基本上都是介绍通用的PDE，没有专门对maxwell equations的。
求教这个证明的思路，感觉对PDE的人来说应该不困难。
但是就是找不到相关的文献或者书本具体针对maxwell equations 讨论的。
真心求高人指教。 |
|
m******o
发帖数: 12 | 10 我们有三个人合写了一个Word 2007文档，里面含有三种公式：
1. MathType输入的公式
2. Word 2007 插入 > 公式 (Insert > Equation)
3. Word 2007 插入 > 对象 > Microsoft Equation 3.0 (Insert > Object >
Microsoft Equation 3.0)
因为不同的人有不同的习惯。但现在要交给Manager修改，Manager只会用Word 2007自
带的公式编辑器（即Insert > Equation）。请问怎么快速把另外两种公式转换成该格
式，不重新敲公式？
谢谢！ |
|
T******s
发帖数: 24 | 11 I am trying to give a self-explained table. I usually give the desciption in
the capition but I cannnot insert an equation in the caption. Can anyone
help me to get around with this problem? Thank you so much ....
\begin{table}
\caption{
{\bf My title Risk} \\
my description comes here with a equation
\begin{equation}
Y= a + b X + e_t
\end{equation}
}
\input{h:/MATLAB/dynamic/d}
\end{table} |
|
t**********r
发帖数: 182 | 12 equation 1:
Yt = Xt-1 + other variables
equation 2:
Xt-1 = Yt + other variables
My question: Xt-1 is lagged variable. so the second equation cannot be
correct. how can i specify the equation? |
|
v******a
发帖数: 45075 | 13 【 以下文字转载自 Joke 讨论区 】
发信人: flyingwawa (flyingwawa), 信区: Joke
标 题: zhuxie 封 equator 在 Basketball (转载)
发信站: BBS 未名空间站 (Fri Feb 2 19:44:12 2007)
发信人: pumpkin2005 (▄︻┻┳═一***), 信区: Basketball
标 题: zhuxie 封 equator 在 Basketball
发信站: BBS 未名空间站 (Fri Feb 2 10:23:30 2007)
发信人: deliver (自动发信系统), 信区:
zhuxie 封 equator 在 Basketball
发信站: BBS 未名空间站自动发信系统 (Thu Feb 1 20:10:22 2007)
【此篇文章是由自动发信系统所张贴】
由于 equator 长期不去赌场消费
被暂时取消在本版的发文权力 365 天。
版主:zhuxie
|
|
l******9
发帖数: 579 | 14 【 以下文字转载自 Statistics 讨论区 】
发信人: light009 (light009), 信区: Statistics
标 题: solve equations of integrals in python
发信站: BBS 未名空间站 (Fri Mar 21 12:21:31 2014, 美东)
I need to solve system equations of integrals in python 3.2.
from sympy import S, Eq, solve, integrals
import sympy as sym
import scipy.integrate as integ
x, b, c, m, v, L, u = S('x, b, c, m, v, L, u'.split())
equations = [Eq(m, integ.quad(xf(x, b, c), L, u))]
def xf(x, b,c):
return x*f(x,b,c)
def f(x, b, c):
return g(x, ... 阅读全帖 |
|
T*******n
发帖数: 493 | 15 \usepackage{amsmath}
\begin{equation}
y=x \tag{12345}
\end{equation}
equation |
|
e*******e
发帖数: 248 | 16 我现在有这样的一个equation:
\begin{equation}
p(t)=e^{\displaystyle j2\pi k f_0(\alpha+t^+)}-e^{\displaystyle j2\pi k f_0
(\alpha-a+t^-)}
\end{equation}
我开始没有用\displaystyle，e的指数显得太小。用了\displaysytle后，e又显得太小
。不知道能不能单独把e的字体搞大点儿。到处查了查，没有找到解决的方法。 |
|
t**********h
发帖数: 100 | 17 在 \begin{equation}...\end{equation} 里面， 当有多行公式是，每一行就自动标上
label,但是我只需要一个label就可以了。好像是 \nolabel, 但是又行不通，所以问
问大家到底怎么办？
先谢谢了！ |
|
h*****g
发帖数: 944 | 18 我现在的latex package, 如果用
\begin{equation}
\end{equation}
来输入数学公式的话，数学公式会自动居中。
如何让一行equation居左？
谢谢！ |
|
g******9
发帖数: 44 | 19 现在的情况是，如果连续两个{equation}之间的vertical space太大了，怎么变小？
\begin{equation}
\end{equation}
谢谢 |
|
h*****g
发帖数: 944 | 20 我现在的问题是
\begin{align}
...............
\end{align}
align了12个equation, 但是latex default是让这12个equation都显示在一页里
这样的话文章搞出来很大空白,如何让第一页显示8个equation, 剩下的放到第二页显示
? |
|
c********r
发帖数: 2227 | 21 Thanks for your post.
My understanding is it can not even give you an estimation.
for statistical copolymer you do not have to consider the dependence of Tg
on
molecular weight, since you will use the Tg for the high molecular
homopolmer.
Same for the Gorden-Taylor equation.
Or an equal question is for two miscible polymers, Will the statistical
copolymer and block copolymers with same weight fractions show same Tg?
If yes, we can get nothing about the block length from the fox equation.
I might... 阅读全帖 |
|
c*****t
发帖数: 520 | 22 我最近粗看了些和dispersive equations相关的内容，对这方面的研究颇为疑惑，想请
了解这个领域的朋友指教。
我看的内容，包括water waves, Schrodinger equations, solitons, inverse
scattering等课题，应该算是和dispersive equations的研究相关吧。
比方说，我在MIT Open Course Ware看到名为Wave Propagation的课程，浏览了讲义。
ocw.mit.edu/OcwWeb/Mechanical-Engineering/2-062JFall-2006/CourseHome/index.
htm
从编号看，这门课是Civil and Environmental Engineering，Mechanical
Engineering 以及Mathematics 这3 个系合开的。涉及了water waves 之类的课题。
另外我看了Mark J. Ablowitz的几本关于solitons等课题的书。
http://amath.colorado.edu/~markjab/boo |
|
c*****t
发帖数: 520 | 23 抱歉，我似乎没有把意思表达清楚。
我想问：以MIT 为例，数学系开的名为Wave Propagation的课程，和系里面研究
dispersive equations的教授的工作，似乎差得很远。
是不是要去学习dispersive equations，即便PDE论文的题目是关于具体的方程的，例
如Schrodinger equations ，Water waves 等课题，也是和物理背景没有什么关系，只
是和Fourier transform 等分析技巧有关的？看应用数学方面的专著，例如上述MIT 课
程讲义，以及Mark J. Ablowitz的书，并不能起到什么帮助？
请了解的朋友指教。非常感谢。 |
|
c*****t
发帖数: 520 | 24 请教parabolic equation收敛到stationary solution 的条件。
Consider parabolic equation
u_t=Lu. (P)
If we know that the second order elliptic equation
Lu=0, (E)
has unique solution v(x), then v(x) is the unique stationary solution of (P).
(We let (P) and (E) have same boundary conditions.)
Under what condition we can say that the solution u(x,t) of (P) converges to
v(x), as t goes to infinity?
In general, if (E) has several solutions v_1(x),...,v_n(x),... 阅读全帖 |
|
w*********o
发帖数: 434 | 25 exactly, appearance of i in front of time derivative matters. that means it
is wave equation instead of difusion equation. |
|
J********i
发帖数: 8 | 26 Could anyone please answer the question -
Do I need to remember the following formula/equation for the NAPLEX?
1. CrCl (cockcroft-gault equation)
2. Calories/gram for TPN
3. BMI
4. IBW
5. BSA
6.Henderson-Hasselbalch equation
7. T1/2
Thank you so much! |
|
l******9
发帖数: 579 | 27 【 以下文字转载自 Statistics 讨论区 】
发信人: light009 (light009), 信区: Statistics
标 题: solve equations of integrals in python
发信站: BBS 未名空间站 (Fri Mar 21 12:21:31 2014, 美东)
I need to solve system equations of integrals in python 3.2.
from sympy import S, Eq, solve, integrals
import sympy as sym
import scipy.integrate as integ
x, b, c, m, v, L, u = S('x, b, c, m, v, L, u'.split())
equations = [Eq(m, integ.quad(xf(x, b, c), L, u))]
def xf(x, b,c):
return x*f(x,b,c)
def f(x, b, c):
return g(x, ... 阅读全帖 |
|
a***d
发帖数: 336 | 28 so you want to find the equilibrium of your equation system?
maybe you can try to estimate coefficients the equations separately as the
first step. Then use other ways (analytical or numerical) to solve the
equation system with estimated coefficients to get the equilibrium.
complicated.
be |
|
l******9
发帖数: 579 | 29 【 以下文字转载自 Statistics 讨论区 】
发信人: light009 (light009), 信区: Statistics
标 题: solve equations of integrals in python
发信站: BBS 未名空间站 (Fri Mar 21 12:21:31 2014, 美东)
I need to solve system equations of integrals in python 3.2.
from sympy import S, Eq, solve, integrals
import sympy as sym
import scipy.integrate as integ
x, b, c, m, v, L, u = S('x, b, c, m, v, L, u'.split())
equations = [Eq(m, integ.quad(xf(x, b, c), L, u))]
def xf(x, b,c):
return x*f(x,b,c)
def f(x, b, c):
return g(x, ... 阅读全帖 |
|
k*****r
发帖数: 21039 | 30 有没有个latex equation editor, 可以直接cut-paste equations as PNG/TIFF to multiple word processors, like MS word, WPS word, and OpenOffice write ? |
|
k*****r
发帖数: 21039 | 31 我在用OpenOffice, 但不喜欢它的equation editor.
现在似乎有个OOoLatex, 可以在OpenOffice Write 里面直接用latex equation.
不过捣鼓半天，还是没有work propoerly. |
|
k*****r
发帖数: 21039 | 32 no, that is not LaTex equation, rather some OpenOffice equation. |
|
c******n
发帖数: 4965 | 33 case only has 2 columns becuse it uses
eqnarray to do that,
I finally got it by changing latex internal
equation number and equation tag |
|
k*****r
发帖数: 21039 | 34 yeah, but...
anyway, just installed OOoLatex package. the inline part seems to work, but
full blown equations still have errors.
anyone used Latex equation in OpenOffice ? |
|
x******g
发帖数: 3952 | 35 Use paste special to paste your equation as picture.
equations |
|
s*******l
发帖数: 60 | 36 Solved the problem after updated the offcie 2007. There is the compatible
issue. The original equation came from the office 2008 for mac.
equations
be |
|
T*******n
发帖数: 493 | 37 Here is a hack for wide equations in two-column layout.
The equations stay where they are supposed to be, but
there may be some spacing problems at page breaks.
You also lose some float functionality because of the use
of the multicol package. See the multicol documentation
for details. The definitions between \usepackage{amsmath}
and \begin{document} can be saved in a .sty file and
loaded using \usepackage{...}.
I think I posted this before. Just run it through LaTeX
and you'll see what it l |
|
i********y
发帖数: 346 | 38 如果不强制加，equation number是自动递增的。但是偶需要手动定义式子的equation
number,请问如何实现，谢谢。 |
|
z***t
发帖数: 121 | 39 我只要\begin{equation} 所有的东东就居中， 怎么能让 equation mode 中东西居左？
谢谢 |
|
z***t
发帖数: 121 | 40 Can I left align all the equations in equation mode? |
|
h*****g
发帖数: 944 | 41 如果我只是让这个document中的其中几个equation居左，而不是让所有的equation都居
左该怎么办？
谢谢 |
|
T******s
发帖数: 24 | 42 Thank you for your reply. I tried that. but it can not center the equation.
I saw many papers in my field having the equations above the table. donot
know how they did that? |
|
i******t
发帖数: 370 | 43 Does anyone know a simple way of typesetting an equation with a text label
flushed left? Something like:
(Mass-energy equivalence) E=mc^2 (equation no.) |
|
a****9
发帖数: 418 | 44 does this work for you?
\begin{equation}
\textrm{(Mass-energy equivalence)}\qquad E&=&mc^2
\label{eq:me}
\end{equation} |
|
S**I
发帖数: 15689 | 45 \documentclass[fleqn]
\begin{equation}
\end{equation} |
|
x******r
发帖数: 367 | 46 Thanks.
Are there any simple Poisson equations that have the analytical solution?
I just download some programs to solve Poisson equations.
But I have no data to verify that the program is correct. |
|
m*******r
发帖数: 3 | 47 Does anyone have the code to solve Kolmogorov forward equation (also called
Fokker–Planck equation) using function PDEPE?
The solution has been applied in diffusion theory in population genetics!
I shall appreciate it very much. |
|
t*****k
发帖数: 390 | 48 【 以下文字转载自 Mathematics 讨论区 】
发信人: trthank (L，是该过去的时候了么), 信区: Mathematics
标 题: 问关于advection equations
发信站: BBS 未名空间站 (Wed Dec 2 00:56:16 2009, 美东)
对于advection equation, u_t + au_x = 0, if a is very large, whether this sys
tem is stiff or not? 是否一定要用implicit method 来做. Thanks! |
|
j******i
发帖数: 6 | 49 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
|
j******i
发帖数: 6 | 50 To anybody who knows black-scholes model and stochastic differential
equation or anybody who knows control theory.
dS=αSdt+βSdB, S denote the price of a stock depends on t,S(t), α is the
drift or rate of return, β is the volatility, B is brownian motion.
How do I incorporate the control parameter γ , and a number “ L “defined
as dN/dS, where N denotes the amount of asset traded and S denote the asset
price so that dS=(αS+γ/L)dt+βSdB
defines a differential equation.
Thank you in advance |
|
