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Using nrnpython and adding new mechanism

Posted: Mon Jul 02, 2007 6:25 am
by arb
I am using python with the connection nrnpython to using neuron. Everything worked great, but now I wanted to add new mechanisms.
For a simple test I downloaded the NMDA.mod file from myfirstneuron from the Neuron web-site and compiled it with nrnivmodl. that works.

now I have a init.hoc that I call by the python functions:
from neuron import hoc

nrn = hoc.HocObject()

nrn.load_file("init.hoc")

my init hoc file contains the cell definition and pointprocesses.

to be able to load the mechanism I put:
nrn_load_dll("i686/.libs/libnrnmech.so")
so it should load the compiled mechanism (nrniv init.hoc works fine)

But I get the message:

dlopen failed -
undefined symbol: nrnmpi_myid


please help!

thank you!

Posted: Mon Jul 02, 2007 3:22 pm
by hines
I am using python with the connection nrnpython to using neuron.
What does that mean?
Are you running python extended with NEURON or are you running nrniv with python embedded. The latter with

Code: Select all

[hines@localhost npy]$ cat dll.py
import hoc
h = hoc.HocObject()
h.nrn_load_dll("/home/hines/neuron/npy2/share/nrn/demo/release/x86_64/.libs/libnrnmech.so")
is working on my x86_64 except for the apparently benign error message:
oc: Inappropriate ioctl for device
nrniv: errno set during call of nrn_load_dll
(I may have to set errno=0 to
eliminate that. At least all the mechanisms seem to have been loaded.). At any rate, I likely will not be able to work on this til I return from CNS at Toronto late next week.

Adding new mechanisms problem with nrn_load_dll

Posted: Mon Jul 02, 2007 5:32 pm
by arb
thank you for this fast answer

python extended with Neuron

I have installed NEURON -- VERSION 6.0.pygetsetcall.23 () with the option --nrnpython

and I am importing neuron like this
from neuron import hoc
nrn = hoc.HocObject()
nrn.nrn_load_dll("..../i686/.libs/libnrnmech.so")

but I still get the error:
dlopen failed -
undefined symbol: nrnmpi_myid

perhaps is a problem with the beta version, but I cannot compile the latest neuron version with the option --nrnpython, I have already found that others had similar problems for the last case.


thanks!
armin