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I Encountered Error Message trying to use dsolve t...

Asked by: Elisha 35
ode parameters dsolve
February 11 2023
0  6

I find it difficult to use dsolve to solve system of ordinary differential equations with assigned parameters and initial conditions. The error message "Error, (in dsolve/numeric) 'parameters' must be specified as a list of unique unassigned names" kept coming up.

Pls see the uploaded equation for more understanding

> 

restart
> 

interface(imaginaryunit = F)

I

 (1)
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I

I

 (2)
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sqrt(-4)

2*I

 (3)
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NULL
> 

Suscep := diff(S(t), t) = theta*epsilon+v__2*S__v(t)-S(t)*lambda-S(t)*(µ+v__1)

diff(S(t), t) = theta*varepsilon+v__2*S__v(t)-S(t)*lambda-S(t)*(µ+v__1)

 (4)
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Vacc := diff(S__v(t), t) = (1-theta)*epsilon+v__1*S(t)-(µ+alpha+v__2)*S__v(t)-(1-w)*S__v(t)*lambda
> 

Immun := diff(V(t), t) = alpha*S__v(t)+`ρ__A`*A(t)+(1-k)*`ρ__Q`*Q(t)+`ρ__I`*(I)(t)-µ*V(t)
> 

Exp := diff(E(t), t) = S(t)*lambda+(1-w)*S__v(t)*lambda-(q__E+delta+µ)*E(t)
> 

Asymp := diff(A(t), t) = delta*a*E(t)-(`ρ__A`+µ)*A(t)+k*`ρ__Q`*Q(t)
> 

Inf := diff((I)(t), t) = delta*(1-a)*E(t)-(`ρ__I`+q__I+`δ__I`+µ)*(I)(t)
> 

Quar := diff((I)(t), t) = q__E*E(t)+q__I*(I)(t)-(`ρ__Q`+`δ__Q`+µ)*Q(t)
> 

init_conds := S(0) = S_0, S__v(0) = S__v*_0, V(0) = V_0, E(0) = E_0, A(0) = A_0, (I)(0) = I_0, Q(0) = Q_0

S(0) = S_0, S__v(0) = S__v*_0, V(0) = V_0, E(0) = E_0, A(0) = A_0, I(0) = I_0, Q(0) = Q_0

 (5)
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sys := {Asymp, Exp, Immun, Inf, Quar, Suscep, Vacc, init_conds}
> 

``
> 

sol := dsolve(sys, numeric, parameters = [`δ__Q`, `δ__I`, a, k, epsilon, v[1], q[E], q[I], q[A], eta[A], eta[Q], rho[A], rho[Q], rho[I], v[2], alpha, mu, delta, alpha, beta, w, lambda, S_0, S__v*_0, V_0, E_0, A_0, I_0, Q_0], method = rkf45)

Error, (in dsolve/numeric) 'parameters' must be specified as a list of unique unassigned names

  
> 

sol(parameters = [delta = .125, `δ__Q` = 0.6847e-3, epsilon = .464360344, `δ__I` = 0.2230e-8, a = .6255, q[E] = 0.18113e-3, k = .15, v__1 = 0.5e-1, v__2 = 0.6e-1, `ρ__Q` = 0.815e-1, `ρ__A` = .1, `ρ__I` = 0.666666e-1, q__I = 0.1923e-2, q__A = 0.4013e-7, `η__A` = .1213, `η__Q` = 0.3808e-2*alpha and 0.3808e-2*alpha = .4, w = .5925, mu = 0.464360344e-4, lambda = 0.1598643e-7, S_0 = 1.0, S__v*_0 = 0.6e-4, V_0 = 0.35e-4, E_0 = 0.5e-4, I_0 = 0.32e-4, A_0 = 0.15e-4, Q_0 = 0.1e-4])

sol(parameters = [delta = .125, delta__Q = 0.6847e-3, varepsilon = .464360344, delta__I = 0.2230e-8, a = .6255, q[E] = 0.18113e-3, k = .15, v__1 = 0.5e-1, v__2 = 0.6e-1, rho__Q = 0.815e-1, rho__A = .1, rho__I = 0.666666e-1, q__I = 0.1923e-2, q__A = 0.4013e-7, eta__A = .1213, false, w = .5925, mu = 0.464360344e-4, lambda = 0.1598643e-7, S_0 = 1.0, S__v*_0 = 0.6e-4, V_0 = 0.35e-4, E_0 = 0.5e-4, I_0 = 0.32e-4, A_0 = 0.15e-4, Q_0 = 0.1e-4])

 (6)
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Evaluate*the*system*at*t = 2
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sol(2)

sol(2)

 (7)
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sol(1)

sol(1)

 (8)
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sol(.1)

sol(.1)

 (9)
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sol(.3)

sol(.3)

 (10)
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sol(.5)

sol(.5)

 (11)
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sol(.7)

sol(.7)

 (12)
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sol(.9)

sol(.9)

 (13)
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sol(1.1)

sol(1.1)

 (14)
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sol(1.3)

sol(1.3)

 (15)
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sol(1.5)

sol(1.5)

 (16)
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> 

 

Download Covid19_Simulation.mw

To find the table values of Nusselt and Skin frict...

Asked by: KIRAN SAJJAN 40
February 10 2023
0  2

odeSys := {diff(Theta(x), x, x)+Pr*(R*(diff(Theta(x), x))*f(x)+Nb*(diff(Theta(x), x))*(diff(Phi(x), x))+Nt*(diff(Theta(x), x))^2), N2*(diff(G(x), x, x))-N1*(2*G(x)+diff(f(x), x, x))-N3*R*((diff(f(x), x))*G(x)-f(x)*(diff(G(x), x))), diff(Phi(x), x, x)+R*Sc*f(x)*(diff(Phi(x), x))+Nt*(diff(Theta(x), x, x))/Nb, (1+N1)*(diff(g(x), x, x))+R*((diff(g(x), x))*f(x)-g(x)*(diff(f(x), x)))-M*g(x)+2*Kr*(diff(f(x), x)), (1+N1)*(diff(f(x), x, x, x, x))-R*((diff(f(x), x))*(diff(f(x), x, x))-f(x)*(diff(f(x), x, x, x)))+N1*(diff(G(x), x, x))-M*(diff(f(x), x, x))-2*Kr*(diff(g(x), x))}; cond := f(0) = 0, (D(f))(0) = 1, g(0) = 0, Theta(0) = 1, G(0) = -n*((D@@2)(f))(0), Phi(0) = 1, f(1) = lambda, (D(f))(1) = 0, g(1) = 0, Theta(1) = 0, G(1) = n*((D@@2)(f))(1), Phi(1) = 0; ans := {};

n := .5; N1 := 0.; N2 := 1.0; N3 := .1; lambda := .1; M := .1; Kr := .1; Sc := 1.0; Nb := .1; Pr := 1.0; Nt := .1; R := .5;

ans := dsolve*{cond, eval*odeSys};

hello these are the pde and Boundary conditions  i want to calculate the value of f''(0) ,Theta(0) and  Phi(0)

what is the proper cammand to get the table values for the given equation
NBVs := [eval(ans(N1*G(x)+(1+N1)*(diff(f(x), x, x))), x = 0), eval(ans(-(diff(Theta(x), x))), x = 0), eval(ans(-(diff(Phi(x), x))), x = 0)];

FEM or FDM for the given pde can i calculate the ...

Asked by: KIRAN SAJJAN 40
February 07 2023
0  2

Hi,

I want to solve system of PDE equations by maple and i dont know how can i write it codes that can solve them for me. Can you create the code for the equation

Thank you

A Maple Programme Code...

Asked by: abiodunowoyemi9 30
February 06 2023
0  2

Good day,
 

1. Please I need your greatest help. Can anyone please help me to run the examples on the attached papers on Maple software?

 2. Also help me to plot the graphs along with the exact solution

 3. If possible with tables

 I tried but did not get the results as expected. I shall be very grateful if I can get assistance from you

 

Thanks