COMPGROUPS.NET | Search | Post Question | Groups | Stream | About | Register

### telegraph equation solution

• Email
• Follow

```How do I solve the so called telegraph equation?

u_{tt} +(a+b)u_t+abu= c^2 u_{xx}
```
 0
Reply mail.plutus (24) 11/28/2006 5:14:09 PM

See related articles to this posting

```steve wrote:
>
>
> How do I solve the so called telegraph equation?
>
> u_{tt} +(a+b)u_t+abu= c^2 u_{xx}
```
 0
Reply mail.plutus (24) 11/29/2006 4:29:59 PM

1 Replies
70 Views

Similar Articles

12/17/2013 12:33:25 PM
page loaded in 44179 ms. (0)

Similar Artilces:

Using the solution of a differential equation and minimizing the solution.
Hi all, I am working in beam physics.I am getting used to mathematica now.But feel little uncomfortable doing few things. Now I solved a differential (simulataneous ) equation in {X''(z),Y''(z),X(z),Y(z)} with four intial conditons and getting the answer for X & Y in interpolating function.I plot it for required z and its all fine and great and FAST!! Question 1: Now I want to find the minimum of this solution X(z).How do i use the function FindMinimum for this interpolating function? Question 2: In the long run I want to find the value of the intial ...

HELP! very hard equations and inequalities seeking for solution / no-solution analysis?
Dear all, I am facing with this super hard problem, please help me solve it or at least give some analysis for no-solution answer: Suppose we have 10 variables: z, a1, a2, a3, a4, a5, a6, a7, a8, a9, where z>0, Here are the equations/inequalities: |z-2*a2-2*a9| < z ; |z - 2*a1| >= z ; |z - 2*a2| >= z ; |z - 2*a3| >= z ; |z - 2*a4| >= z ; |z - 2*a5| >= z ; |z - 2*a6| >= z ; |z - 2*a7| >= z ; |z - 2*a8| >= z ; |z - 2*a9| >= z ; a1+a2+a3+a4+a5+a6+a7+a8+a9 = 3*z ; a1-a2-a4+a5=0; a1-a3-a4+a6=0; a1-a2-a7+a8=0; a1-a3-a7+a9=0; I hope to find analysis saying that t...

solutions of a equation
Hi I have one equation. aX^3+bX^2+cX+d=0 There should be three solutions in this equation. Is there any function to calculate the solutions? Thanks! Young Ryu wrote: > I have one equation. > aX^3+bX^2+cX+d=0 > There should be three solutions in this equation. Is there > any function to calculate the solutions? Are a, b, c, and d constants? Are they scalars or vectors? Is X a matrix? If a, b, c and d are all scalar constants and X is scalar, then X = roots([a b c d]); -- Q = quotation(rand); if isempty(Q); error('Quotation server filesystem problems') else spri...

Any way to vectorize an equation whose current solution depends on it's previous solution?
Is there a way to vectorize the following equation? x(1) = some number x(i) = a(i) - b(i)*c(i-1) / x(i-1) Thanks, J On 19 Okt, 15:25, "Jason " <mrg...@hotmail.com> wrote: > Is there a way to vectorize the following equation? > x(1) = some number > x(i) = a(i) - b(i)*c(i-1) / x(i-1) No. This is an iterative or recursive algorithm, which can not be vectorized. Rune In article <1192801357.111479.181510@y27g2000pre.googlegroups.com>, Rune Allnor <allnor@tele.ntnu.no> wrote: >On 19 Okt, 15:25, "Jason " <mrg...@hotmail.com> wrote: >&g...

solution to undetermined equation
hi i have a set of undetermined linear equations with unknowns 13 and set of equation=3 my equation formulates as Ax=min with the constraint that the sum of unknowns equals the number of unknowns in my case x1+.....x13=13 is it possible in matlab Regards, "Shama " <shammashahbaz@yahoo.com> wrote in message <fiomhb\$hb2\$1@fred.mathworks.com>... > hi > > i have a set of undetermined linear equations with > unknowns 13 and set of equation=3 > my equation formulates as > > Ax=min > > with the constraint that the sum of unk...

solution of the Riccatti equations
Hi I am an electrica engineer,i am developping a project and i need an algorithm to solve the riccatti equation,unfortunately,up to now,i have not find that algorithm in the web.please help me.the problem is: I have used the Hamiltonian technique to find the optimal control from a given cost function.the solution is of the form: U(k)=-K*X(k)+U0; To find the feed back gain "K",I need a solution of the riccatti equation.please help me.Thank you Raoul "Raoul" <cradle1976@hotmail.com> wrote in message news:keobvyzp2jq3@legacy... > Hi > I am an electrica engineer,i...

SYMBOLIC EQUATION SOLUTION
I wrote a very simple following matlab code to solve a set of equations: syms f a2 a3 a4 b2 b3 b4; G1=(1+a2*f^2+a3*f^3+a4*f^4); G2=(1+b2*f^2+b3*f^3+b4*f^4); G=(G1+G2)-2*G1*G2; G=collect(G); F=int(G,f,0,1/2); %integrates G(f) over 0 to 1/2 F=subs(F,{a2,a3,a4},{20.25,-64,55}); S=solve('F=1','b2+b3/2+b4/4+2=0','b2=0'); When I run this code F comes out to be: -517/40320*b4-229/7168*b3-283/3360*b2-3/16 So F consists of three elements b2,b3,b4. Last line of the code returns S as [emptysym] but theore should be solution as I found out with the help of a calculator. Can someo...

Solution partial differential equation
hello I have the following partial differential equation with two variables: T(xx)=second order degree of differential T respect to x and T(y)=first order degree of differential T respect to y T(xx) -x*T(y)+1=0 Can I get the general solution of this equation? T(x,y)=....... I have not boundary conditions neither initial condition. Thanks ...

solution to a system of transcendenrtal equations
Hi all we use solve command to solve two or more algebriac equations. But what if I have equations in transcendental functions.Is there another solver to solve these equations (in two independent variables) e.g if I have one equation in exponential function and other is also not algebriac? I have two variables to be calculated. is there any suitable command in Matlab to tackle these non algebriac equations. thanks You can solve it numericly with fzero. fzero is searching of zero of function of one variable. So you need to convert system odf equations to one equation with one variable. ---...

Positive solution for linear equations
I am trying to find the solution for a series linear equations: Ax =B, where A is a n by m matrix and B is a vector . I use the IDL function SVDC but I wish the solution x to be positive vector. How can I do so? Thanks, Eran On Apr 12, 6:53=A0am, erano <eran.o...@gmail.com> wrote: > I am trying to find the solution for a series linear equations: Ax =3DB, > where A is a n by m matrix and B is a vector . > I use the IDL function SVDC but I wish the solution x to be positive > vector. > How can I do so? > Thanks, > Eran What's a positive vector? Vince Hradil writ...

Solution of coupled differential equations
Hello, I like to build up a model of a tubular reactor that outputs the concentration profile and the temperature profile along the axis variable. It is is easy to calculate each of them seperately with the ode45 solver, if the differential equations do not depend on each other. But how can I couple the differential equations in matlab. The ongoing reaction (reaction enthalpy!) influences the temperature profile an the change in temperature influences the reaction rate. Can anyone give me an advise? Thank you in advance Greetings Daniel The coupled ODEs can be solved by ode45 in exactly ...

Iterative solution to a transcendental equation.
Thank you for having the informative website, that as a new user, I am enjoying. I am in the process or porting over into MATHEMATICA a long program that describes non-linear processes in optical fiber amplifiers=97an area of my specialty. There is a transcendental equation in this long program that, written in dimensionless form, shows the amplified signal in the cladding-pumped fiber. The particular snippet of code is in a nb file (I prefer to use the nb as a front end), but I transcribe it below. As you shall see, this equation is unlike the examples in the manual, an...

Re: Numerical solution of differential equation
Dear Arturas, Many thanks for your kindness. Yes it is the classical Skyrmion. I know your papers on Skyrmions. It is surely nice that an expert can share his codes. Best regards, susy ...

problems with solution of step equations #2
Dear all, I have to solve the equation for the following problem: Y=h(x) x>b else Y=g(x) x<=b. When i use fsolve function, i put the evaluation function as: function f=fun(x) if x>b Y=h(x) else Y=g(x) f=Y; Then i use: fsolve('fun',x0).But unfortunately i could not solve this equation correctly. I only get results for Y=g(x), which means the evaluation is valid only for X<=b. Does any one know how to solve such step equation? Looking forward to your answers as soon as possible. Thanks a lot. "Yueping Xu" <yuepingxu@gmail.com> wrote in message <fh...

Numerical solution of a third order equation
I tried the following program: a = 3; b = 2 ; c = solve('a*x^2+b*x^3-5=0') ; all I get is a symbolic solution. How can I obtain a numerical solution to such equations? Please help! do you really need Matlab to solve a 3rd order equation?!? anyway, the dumbest way c = double(solve([num2str(a),'*x^2+',num2str(b),'*x^3-5=0'])); Utzli Gutzli wrote: > > > I tried the following program: > > a = 3; > b = 2 ; > c = solve('a*x^2+b*x^3-5=0') ; > > all I get is a symbolic solution. > How can I obtain a numerical solution to such equation...

Compiler possible solutions to equation-handling
I am creating some C compilers and my own language for CBM computers. I am looking for a good, yet efficient method to handle equations. cc65 seems to push the left argument on the stack, then operate on it with the right argument. I have my own method, but it is too complex to run under an 8-bit computer. Anybody have any suggestions? Harry Potter <maspethrose7@aol.com> wrote: > I am creating some C compilers yawn -- -=[]=--- iAN CooG/HokutoForce ---=[]=- AAcckk!! II''mm iinn hhaallff dduupplleexx On 8/8/08 2:12 PM, in article g7i2do\$20u\$1@aioe.org, "iAN CooG&q...

ode45 question
Hello.. wondering if anyone can help out. I'm trying to solve an ode final value problem. So for e.g. solving dydt=f(y,t) for t0 (initial time) to tfinal (final time) with y(tfinal)=yf. I tried solving backwards in time using tspan = LINSPACE(tf1,t01); ode45(@(t,Y) odefun(t,Y,vars),tspan,yf); So my timespan is backwards. I got a very bad solution (very large) but when I solved it as an initial value problem tspan = LINSPACE(t01,tf1); ode45(@(t,Y) odefun(t,Y,vars),tspan,yf); The solution seemed reasonable. Just wondering if I "flipped" the result of t...

regarding solution of more than 2 coupled equation
i want to solve four coupled differential equation by runga kutta method.....which are of first order and some are of second order terms...these terms are of mass flow rate, pressure ,temperature and position in fluid flow in channel... On 30 Aug., 20:02, "Prabhakar Rawat" <prabhakarra...@gmail.com> wrote: > i want to solve four coupled differential equation by runga kutta method.....which are of first order and some are of second order terms...these terms are of mass flow rate, pressure ,temperature and position in fluid flow in channel... If they are partial differen...

Fitting the solution of a differential equation to a data set
Hi list, given a set of data (e.g. {x,y} pairs) and a theoretical model described by a differential equation (with some free parameters) that cannot be solved analytically, I am searching for a way to somehow use Mathematica to fit the numerical solution of the equation to the data set. Unfortunately I failed to utilize FindFit and NDSolve on this behalf (which might very well be due to my lack of experience with Mathematica...). Any suggestions on how to do this? Kind regards, Timm Many thanks to all of you. All the answers provided useful ideas and interesting points for ...