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Question: Store values for numerical solution

Question:Store values for numerical solution

Nick_99 55 Maple
ode parameters dsolve numeric differential-equations
December 01 2020
1

I have a piece of code that solves a differential equation numerically and plots the solution, but I also want to store my values for the solution so that I can later call them easily. I want to be able to save my values for xphi for all t from 0 to 11 - not necessarily with the same variable name, it could be some k(t) - so that later when I type eg k(10) Maple gives me the value of xphi at t=10. I assume the code only requires a slight modification, but still I haven't been able to find a way to do this. Here is the corresponding piece of code. Thank you in advance.

> 

xodephi := {diff(x(t), t) = 16250.25391*(1 - (487*x(t))/168 + 4*Pi*x(t)^(3/2) + (274229*x(t)^2)/72576 - (254*Pi*x(t)^(5/2))/21 + (119.6109573 - (856*ln(16*x(t)))/105)*x(t)^3 + (30295*Pi*x(t)^(7/2))/1728 + (7.617741607 - 23.53000000*ln(x(t)))*x(t)^4 + (535.2001594 - 102.446*ln(x(t)))*x(t)^(9/2) + (413.8828821 + 323.5521650*ln(x(t)))*x(t)^5 + (1533.899179 - 390.2690000*ln(x(t)))*x(t)^(11/2) + (2082.250556 + 423.6762500*ln(x(t)) + 33.2307*ln(x(t)^2))*x(t)^6)*x(t)^5, diff(xphi(t), t) = 5078.204347*x(t)^(3/2), x(0) = 0.03369973351, xphi(0) = a}:  #xphi(10.92469316) = 0}:
> 

sol := dsolve(xodephi, parameters=[a], numeric):
> 

ff:=proc(A)
  sol(parameters=[A]);
  eval(xphi(t), sol(10.92469316))
end:
> 

A:=fsolve(ff);
sol(parameters=[A]);
sol(10.92469316);

-467.1843838

  

[a = -467.1843838]

  

[t = 10.92469316, x(t) = HFloat(0.061040830524973895), xphi(t) = HFloat(1.6909911249030074e-9)]

 (1)
> 

plots:-odeplot(sol, [t,xphi(t)], t=0..11);

 
> 

plots:-odeplot(sol, [t,x(t)], t=0..11);

 
> 

 

 
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