orbithunter.core.Orbit.costgrad

Orbit.costgrad(eqn=None, **kwargs)

Matrix-vector product corresponding to gradient of scalar cost functional \(1/2 F^2\)

Parameters

eqnOrbit

Orbit instance whose state is an evaluation of the governing equations

kwargsdict

extra arguments for rmatvec method.

Returns

gradient :

Orbit instance whose state contains (dF/dv)^T * F ; (adjoint Jacobian * eqn)

Notes

Withing optimization routines, the eqn orbit is used for other calculations and hence should not be recalculated; this is why eqn is passed rather than recalculated.

Default cost functional is \(1/2 F^2\).