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I am writing a procedure that takes the "output" of a call to dsolve (with the options numeric and listprocedure and without specifying a range of integration) as an argument ('dsol') together with a minimally acceptable range of integration ('tf'). The output of the procedure is either the input 'dsol' itself, if dsolve has been able to integrate from 0 to 'tf', or a modified version where the initial conditions have been modified.

Say I want to integrate an ode system [u,v,w...

I want to solve the position of a bal with a variable angel of the start velocity. I want to know which angle I have to take when the ball must be in a fully known position (5.44 , 1.60).I must also take the friction into account.

Therefore I have a system of equitations that I can solve with dsolve if I fill in the angle (in degrees).

> dsolve(eval(stlsl,angle = angeltest), numeric);

It gives me back values in x(t) and y(t). But know I want to make...

Hi!

I am bothered by an error that I don't understand. I am trying to write a procedure to solve numerically a delay differential equation "step by step" (for example y'(t)=y(t-1))

here is my code

restart;

y[0]:=t->t; #my initial condition on [-1,0]

p:=dsolve({D(x)(t)=y[0](t-1), x(t0)=x0}, x(t), numeric, parameters=[t0, x0]);

p(parameters=[0,y[0](0)]);

y[1]:=t->op(2,op(2,p(t)));  #y[1](t) is the value of p(t) but in a "readable" format

Hello,

I am working on a physics problem that involves a bead on roating hoop. You need to use Lagrangians to solve this problem but this is not where i am strugling. My school expects us to use maple because it is the program the provide but none of the teachers know how to usem it (they use mathmatica) so they cant help us. We have the equation: θ"= [ω²*cos(θ)-(g/R)]sin(θ) and the initial cond. θ'(0)=0 and θ(0)=θ

hi

considering the following ode

eq1 := .6740221708*(diff(f(x), x, x, x))+f(x)*(diff(f(x), x, x))+1-(diff(f(x), x))^2

i solve it by

sol := dsolve({eq1 = 0, f(0) = 0, D(f)(0) = -1.2, (D(f))(b) = 1}, numeric);

this give me one solution but i know that this ode have dual solutions. how can i found all solutions of ODE.

thanks for youe attention in advance

strange.mw

Hi,

i have a question concerning dsolve. I think i typed two identical lines however maple just seems to accept one of these. I am slightly confused. Any suggestions about what might have gone wrong here?

Best regards

I have a column vector of lists. FWIW, it was generated by numerically solving an ODE and then map-ping the solution over a vector with values for the independent variable, like "yt:=map(solnn,xv)" where xv is a column vector with floats and solnn is the result of a dsolve(...,numeric). Each element of the solution vector yt has the form [t=..., y(t)=..., d/dt(y(t))=...] and has the type List.

I want to extract the solutions for y(t) (i.e. the numbers only) into a new...

I need some help...i need a solver using the Runge-Kutta method adaptive size control, to solve a sytem of 5 diff eq's, all of them are interlinked...

And 

Say that dsolve numeric produces a results, called Solution, Now ex  solution(0)=1, and in general solution(t) can be evaluated, now, i want to use this, in E(t)=2*solution(t), in a plot, thus...

plot(E(t),t=0..100,....), but returns the error....

Hi.

I can explain my question on the simplified example:

sol1 := dsolve({diff(x(t), t) = x(t), x(0) = 0.0}, numeric); 

func := q -> op(2, op(2, sol1(q))); 

dsolve({diff(z(t), t) = func(t) * z(t), z(0) = 0.1});

But i take a throw. It is clear, because, I try to call op(2, sol1(t)). Which way I whould use to solve my problem?

I am trying to solve a tricky system of diff eq....can somebody point me in the right direction, the error message is involved with the initial conditions..

Hey there,

i have a differential equation in the form below and the expression c1*x(t) should only be positive. Has someone an idea how to solve this problem?

Hello,

I'm new to Maple and am using it to solve linear and non-linear differential equations.

I can solve and plot linear DEs using a couple of methods. Im trying to solve a non-linear DE and i could find the series solution using dsolve. But given certain initial conditions, is there any way to plot or see the nature of the behaviour of the DE? I just want to see how the DE will look like maybe for certain points up to a certain level of accuracy. Is there any way to do that?

Hello.

for one of my projects I require to solve differential equations I have obtained from an euler-lagrange system.

I solved them and obtained values of angles and their derivatives as listprocedures. I want however to be able to calculate values for different speeds noted as vx2 and vy2 as well as the angle of the speed verctor wich would be in that case arctan(vy2/vx2). It doesn't seem however that maple is going to do that. It gives me a pretty huge message...

I am fairly new to Maple and trying to understand the dsolve command for numerical solutions and plotting graphs of radial distances and trajectory plots.

This is my code below. All of it successfully brings up a solution apart from the very last command and I don't understand why it is not working. 

I believe the last plot is plotting a trajectory plot but I am not sure. I am meant to use the solution to plot the trajectory plot (X(t),Y9t))=(r(t...