On Tue, Oct 5, 2021 at 12:42 AM Wang Jingyuan <[email protected]> wrote:

Dear Sir or Madam,

I am a student of the University of Macau, I am trying to learn PETSc and I have two questions about the TSIRK.

1.PETSc 3.16.0 adds “irk" for the TSType and it offers many options like TSIRK1BEE, TSIRK2C, TSIRK2D, TSIRK2E, TSIRK3, TSIRKL2,

The types you mention above do not exist. For instance, the first one "TSIRK1BEE" is actually https://petsc.org/main/docs/manualpages/TS/TSARKIMEX1BEE.html

I am not sure how to use them and if only Gaussian points can be used (Radau or Labatto may not offered).

There is currently only one IRK type, which is the Gauss method.

2.Maybe there is a similar option to implement the fully implicit Runge-Kutta methods in PETSc 3.15 or other previous versions? For example, if I want to solve a time dependent problem with a butcher table like below, do I need to input it by myself?

Thank you very much for your help.

I do not understand your question. IRK is only present is 3.16 Thanks, Matt

Best regards, Wang Jing-Yuan

-- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>