DifferentialEquation solvers not giving desired output

[John_Gibson]

It’s not really possible to give specific advise without a more definite problem description, i.e. a complete but minimal working example that exhibits a clear-cut error. Generally speaking, rather than checking the Julia’s output against R’s output, it would be better to find a closely related problem with known closed-form solution, and check whether the Julia solution converges towards the closed-form solution at the expected rate.

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