[petsc-dev] TSBASICSYMPLECTIC

[Jed Brown]

Matthew Knepley <knepley at gmail.com> writes:

> On Tue, Sep 11, 2018 at 10:32 AM Zhang, Hong <hongzhang at anl.gov> wrote:
>
>> A few related discussions can be found at
>> https://bitbucket.org/petsc/petsc/pull-requests/1108/rename-bsi-to-symplectic/diff
>>
>> In addition, what we have in PETSc now is "Basic Symplectic Integrators"
>> as introduced in Ernst Hairer's article
>> https://www.unige.ch/~hairer/poly_geoint/week2.pdf .
>>
>> Other types of symplectic methods such as symplectic Runge-Kutta use
>> different tableaus and cannot be implemented in the same framework as the
>> basic one. So when naming this particular type of symplectic methods, we
>> think it is better to be specific than general.
>>
>
> All symplectic integrators need the support for splitting into two fields,
> and they all (I think) offer similar guarantees.

Gauss Runge-Kutta (including implicit midpoint) is symplectic and does
not require any splitting.