verry.integrate.VarEqSolver#

class verry.integrate.VarEqSolver#

Bases: ABC

Abstract base class for solvers of variational equations.

This class is usually not instantiated directly, but is created by VarEqSolverFactory.

Variables:

  • t (Interval) – Current time.

  • jac (IntervalMatrix) – The value that the solution of variational equations takes at t.

Warning

The values of t and jac are undefined if solve() has not been invoked or if the previous execution resulted in failure.

abstractmethod solve(fun, t0, t1, series)#

Solve variational equations.

Parameters:

  • fun (Callable) – Right-hand side of the system.

  • t0 (Interval) – Current time.

  • t1 (Interval) – Next time.

  • series (Sequence[IntervalSeries]) – Current interval series.

Returns:

  • r0 (bool) – r0 is True if and only if t and jac are successfully updated.

  • r1 (str | None) – r1 is None If r0 is True; otherwise, r1 describes the reason for failure.

Notes

The updated t might not be equal to t1 even if r0 is True. The only assumption that can be made is that t is included in t0 | t1.