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convergence failed repeatedly or with |h|=hmin : err=-7

Posted: Thu May 07, 2020 6:38 am
by Junichi
I got an error. I replicated the same model with different coordinates in the same space as the original one.
I tried to look at the change in potential when I gave a certain stimulus to soma and got an error.

CVode-- At t = 0.0449442 and h = 7.61676e-11, the corrector
convergence failed repeatedly or with |h| = hmin.

CVode 0x7f8bc0c132a0 soma[0] advance_tn failed, err=-7.
/Applications/NEURON-7.8//bin/nrniv: variable step integrator error near line 1
and others

if anyone knows about this error,I would appreciate it if you could tell me.
I'l send a zip file directly to anyone who comments for more information.

Re: convergence failed repeatedly or with |h|=hmin : err=-7

Posted: Fri May 08, 2020 5:02 pm
by ramcdougal
The integration advance failed, even when it tried using a really tiny timestep.

One possible cause of this is when some of your state variables have found themselves in an invalid place. You could try reducing the atol to see if that helps, because it'll force the system to more carefully track values before the time when things failed and maybe you'll never enter that domain.

What happens with fixed step integration?