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I want to find the diffrential equation of

Dear All,

Thanks for the previous support and help.

I am trying to solve a poisson equation, but I am getting Bessel function in the solution. Derivation of this equation with respect to 'r' gives more complex form of Bessel function.

Actually I am not sure should I continue with the problem and Maple will take care of everything or I have to modify in the solution.  

Equation 9 and Equation 11 needs to...

Hi,

I have n second order differential algebriac equations (symbolic). I need to convert this system to [A]{X''} + [B]{X'} + [C]{x} + D =0,  where X is the column vector containg the variables and A,B,C,D are the coefficent matrices of X'', X',X and the constant term matrix respectively.

Is there a way to generate this matrices in Maple?

Thanks.

erec :=  mu Q(n + 1) - (n + mu) Q(n) + n Q(n - 1);
with(gfun);
opoly := rectodiffeq(erec, Q(n), f(z));

Error, (in gfun:-rectodiffeq) invalid input: getname expects its 1st argument, yofz, to be of type function(name), but received (z(z)*mu(z)*_C[0](z)-mu(z)*_C[1](z)*z(z)-mu(z)*_C[0](z))/(z(z)*mu(z)-mu(z))

how to rewritten the PDEs to the matrix form like the following in Maple

I  used the DEtools package recently.

When working in a differential algebra with _Envdiffopdomain=[Dt,t] maple still returns something like Dt t^2. I would like him instead to assume, that Dt= dt/t and rewrite it as 2t + t^2 Dt. How can I achieve this behavior?

Hi

I have a problem with an assigment for a Marine Construction claass:

Solving the non-dimensional vibration equation numerically (Eq. 2.1). To this end, implement the following transformation:

Z = dX/dT

Eq 2.1: diff(X(T), T, T)+a*(diff(X(T), T))+b*X(T) = C*(1-(diff(X(T), T)))*abs(1-(diff(X(T), T)))*sin(W*T)

I've tried to do the following:

> dsolve(diff(X(T), T, T)+a*(diff(X(T), T...

Hello, I have tried to solve a system of ODE about the gyroscope for a week. I have entered the following commands : >eq1:=(l^2+r^2/2)*(sin(theta(t))^2*diff(diff(psi(t),t),t)+2*diff(psi(t),t)*diff(theta(t),t)*cos(theta(t)))-r^2*(cos(theta(t))*diff(psi(t),t)+omega(t))*diff(theta(t),t)=0;>eq2:=(l^2+r^2/2)*(diff(diff(theta(t),t),t)-(diff(psi(t),t))^2*sin(theta(t))*cos(theta(t)))+r^2*(diff(psi(t),t)*cos(theta(t))+omega(t))*diff(psi(t),t)*sin(theta(t))=g*l*sin(theta(t)); >eq3:=diff(diff(psi(t...

Hi,

Currently I have to deal with this nonlinear differential equations. The "Newton iteration is not converging" is the main problem. Could anyone propose some solutions?

Thanks a lot.

-EM*iner*(diff(f(x), `$`(x, 4)))-(3/2)*EM*A*nonln*(diff(f(x), `$`(x, 2)))*(diff(f(x), `$`(x, 1)))^2+u*EM*A*nonln*(9*(diff(f(x), `$`(x, 1)))*(diff(f(x), `$`(x, 2)))*(diff(f(x), `$`(x, 3)))+3*(diff(f(x), `$`(x, 2)))^3+(3/2)*(diff(f(x), `$`(x, 1)))^2*(diff(f(x), `$`(x, 4...

ex1 := {
evalDG( d(x) = w1*e1 + w2*e2),
evalDG(d(e1) = w12*e2 + w13*e3),
evalDG(d(e2) = -w12*e1 + w23*e3),
evalDG(d(e3) = -w13*e1 - w23*e3)
};
ExteriorDerivative(ex1);


> ex1 := {evalDG(d(e1) = w12*e2+w13*e3), evalDG(d(e2) = -w12*e1+w23*e3), evalDG(d(e3) = -w13*e1-w23*e3), evalDG(d(x) = w1*e1+w2*e2)}; ExteriorDerivative(ex1);
{d(e1) = w12 e2 + w13 e3, d(e2) = -w12 e1 + w23 e3, d(e3) = -w13 e1 - w23 e3,

  d(x) = w1 e1 + w2 e2}

Could you give examples of differentiate differential form or integrate differential form using maple?

How to solve a set or a system of differential equations in maple for motion with Schwarzchild metric?

************** Schwarzchild metric *****************
with(tensor):
coord := [t, r, theta, Phi]:

g_compts:=array(symmetric,sparse,1..4,1..4):

g_compts[1,1]:=1 - 2*G*M/(r*c^2):
g_compts[2,2]:=-(1 - 2*G*M/(r*c^2))^(-1):
g_compts[3,3]:=-r^2:
g_compts[4,4]:=-(r^2)*sin(theta)^2:

g1 := create([-1,-1], eval(g_compts)):

alpha := vector([cos(theta), sin(theta), sin(k*theta)]);

alpha1 := map(diff, alpha, theta);
alpha11 := map(diff, alpha1, theta);

with(linalg):
cr := multiply(alpha1, alpha11)/simplify(multiply(alpha1, alpha1));

F := vector([0, 0, -m*g]);
c := multiply(F, alpha1/simplify(multiply(alpha1, alpha1)))/m;

motion := diff(f(theta), theta$2) + cr*diff(f(theta), theta)^2 = c;

pdsolve and dsolve not work, how to solve above motion equation with maple?

I am trying to solve a piecewise differential equation of the following form:

FOI := diff(r(x), x) = piecewise(r(x) < 0, 1, r(x) > 0, 0)
dsolve({FOI, r(0) = -1})

but MAPLE returns an error stating

Error, (in dsolve) when calling '`property/ConvertProperty`'. Received: 'real is an invalid property'

I do not know what to make of this. I have tried playing around with assumptions...

Hello,

I’m just toying around with diff(), dsolve(), and, as it happens, also with pdsolve(). Let’s say I have an equation as the following:

DF := (diff(f(x, y, t), `$`(x, 2)))*omega+(diff(f(x, y, t), `$`(y, 2)))^2+diff(f(x(t), y(t), t), t) = 5;

A function f, depending on x, y and t where x and y also depend on t. I multiply the second partial derivative of f by x with ω, add it to the square of the second partial derivative of f by...