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Input Impedance and CVODE

Posted: Mon Jun 27, 2011 3:38 am
by matiasm
Hi,

I have been trying to get the .compute(0.5) working to do some impedance measurements. I have read: https://www.neuron.yale.edu/phpBB2/viewtopic.php?t=771 and there is a line saying:

sets origin for impedance calculations
zz.compute(FREQ, 1) // takes the impedance contributions of
// gating state differential equations into account
// but requires mechanisms to be compatible with CVODE

What does "requires mechanisms to be compatible with CVODE" mean? I am trying to run a simple code similar to the one on this tutorial and I get an error message:
nrniv: spike cannot be used with CVODE

I am using a mechanism called spike, why would this not work with .compute? how can I get around this? I would like to compute input impedances for a few frequencies.

Thank you

Matias

Re: Input Impedance and CVODE

Posted: Mon Jun 27, 2011 11:36 am
by ted
The proper term would be "adaptive integration" but CVODE is the name of the adaptive integrator that was first incorporated into NEURON, and the name stuck. You'll find more about it here, including a suggestion of what is required for a mechanism to be compatible with adaptive integration
http://www.neuron.yale.edu/neuron/stati ... cvode.html
For more information see
http://www.neuron.yale.edu/neuron/stati ... l#Channels

Compiling mod files produces a series of messages that will include warnings about mechanisms that are not compatible with CVODE. They zip past very quickly, so you may have to scroll back to find them.

Re: Input Impedance and CVODE

Posted: Mon Jun 27, 2011 7:21 pm
by matiasm
Excellent thank you very much. I will try edit my mod files and see.
Thanks

Matias