[Users] Negative timesteps with timestep_method="courant_speed" and terminate="time"

[David Radice]

Hello,

I have experienced a curious problem when trying to use

	Time::timestep_method = "courant_speed"

with

	Cactus::terminate = "time".

What happens is that, after the final time is reached, the timestep
becomes negative, afterwards the code quickly crushes (my equations are
not time-reversible and I guess that dt >= 0 is also assumed in many
other parts of the code)...

The attached patch for the Time thorn fixes the problem, even tough I am
not exactly sure on why the commented-out part of the code leads to the
problem: it would seem to me that cctkGH->cctk_time should always be
less then cctk_final_time when this routine is executed...

Do you have any idea of what is going on?

David


-- 
David Radice
Max Planck Institute for Gravitational Physics
Albert Einstein Institute
Am Muehlenberg 1
D-14476 Potsdam
Germany

Tel    : +49 331 567 7242
Fax    : +49 331 567 7499
Room   : 1.64
E-Mail : david.radice at aei.mpg.de 

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