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Warning: Failure at t=4.509803e+01. Unable to meet integration tolerances without reducing the step size below the smallest value allowed (1.136868e-13) at time t.

Can anybody explain what this means?

- Thread starter eurekameh
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- #1

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Warning: Failure at t=4.509803e+01. Unable to meet integration tolerances without reducing the step size below the smallest value allowed (1.136868e-13) at time t.

Can anybody explain what this means?

- #2

SteamKing

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In order to diagnose the problem in more detail, you should probably post the ODE you are trying to solve.

- #3

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mu = 398600.64;

dxdt_1 = x(2);

dxdt_2 = (-mu/x(1)^3)*x(1);

dxdt = [dxdt_1;dxdt_2];

It's a second-order ODE and I'm trying to solve it from the time interval of 0 to 28800. When I lower this time interval to something like 50, the program seems to work fine, but anything higher than that, it stops to converge. Here is my code to run it:

t = 0:28800

[t x] = ode45(@test,t,[1000;-7]);

- #4

SteamKing

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I don't have the ODE you are trying to solve, only your reformulation for Matlab.

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- #6

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Do you know why it's not converging?

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