Search found 220 matches

by Raj
Mon Aug 29, 2005 7:43 am
Forum: Modeling networks
Topic: Hf Stimulus Network Performance: Event Delivery or Pointers?
Replies: 10
Views: 11832

Hf Stimulus Network Performance: Event Delivery or Pointers?

One thing we know for sure: the overhead for numerical integration is a lot more than the overhed of the event delivery system. If you need to be convinced, compare run times for a net of integrate and fire cells vs. a net with the same architecture that uses single compartment hh neurons connected...
by Raj
Thu Aug 25, 2005 1:00 pm
Forum: Modeling networks
Topic: Hf Stimulus Network Performance: Event Delivery or Pointers?
Replies: 10
Views: 11832

Re: local variable time step with large simulations

Dear Bill, Ted, Hines, I tried to use a fixed timestep but found the behaviour to be qualitatively different from the variable timestep, which makes me hesitant about using it, but the reference passed may give clues whether switching to fixed timestep is a viable option. The validity of graded PSP'...
by Raj
Thu Aug 25, 2005 7:41 am
Forum: Modeling networks
Topic: Hf Stimulus Network Performance: Event Delivery or Pointers?
Replies: 10
Views: 11832

Hf Stimulus Network Performance: Event Delivery or Pointers?

Dear Forum, Background: I have been working on a large network of 1028 3 compartment pyramidal neurons + 256 1 compartment interneurons. The model uses the event system for communication between the neurons. Because the synapses are non-linear, a synapse is needed for every connection. Two cells hav...
by Raj
Thu Aug 25, 2005 3:55 am
Forum: Getting started
Topic: record data
Replies: 1
Views: 3501

Re: Record Data

I think you are printing the vector before you do the run and then it is empty. Try entering the last line after running the simulation or if you work from a file add a run() statement before your last line. In contrast to the vec.record(&var) statement which marks the vector as an object in which t...
by Raj
Tue Aug 23, 2005 1:37 pm
Forum: Getting started
Topic: first step in neuron
Replies: 8
Views: 13697

Editors with Syntax Highlighting

Just to offer you another option, which also has tabs but with which I can offer syntax highlighting of hoc and mod language reserved words. Creditor: http://www.praven3.com/credit/ Just install CREditor and save the following as CREditHgl.INI in the directory where you installed/unpacked CREditor. ...
by Raj
Tue Aug 23, 2005 10:25 am
Forum: Other questions
Topic: Ramped current injection
Replies: 3
Views: 5299

Re: Ramped current injection

Another link to try:
http://www.neuron.yale.edu/neuron/stati ... bforc.html

I vaguely remembered seeing your problem solved in a tutorial, the link above to "Model Control: Arbitrary forcing functions" is that tutorial.
by Raj
Tue Aug 16, 2005 9:00 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Stability of steady state approximation
Replies: 3
Views: 5912

Re: Stability of steady state approximation

Unfortunately the corrected code, although better and less prone to future bugs, does not solve the stability problem. I made a test set http://www.vanelburg.net/neuronforum/TestSet_Stability.zip which comes without the complications of my complete simulation. The dynamical mechanism seems stable. T...
by Raj
Tue Aug 16, 2005 6:56 am
Forum: MSWin
Topic: Possible solution for: oc> Cannot allocate memory
Replies: 3
Views: 5715

Possible solution for: oc> Cannot allocate memory

If running NEURON on MSWin you run into the message "Cannot allocate memory" while you still have a large amount of memory available, it is probably caused by the maximum program size of applications run under cygwin. Cygwin's maximum program size can be adjusted with cygwin's regtool: http://www.cy...
by Raj
Tue Jul 19, 2005 4:59 am
Forum: Modeling networks
Topic: It is possible to have Axo-Axonic & Dendro-Dendritic syn
Replies: 2
Views: 4944

Non axo-dendritic synapses

In NEURON the axon or soma section has no special status. It should therefore not pose any problems to make synaptic signals from dendrites to axons. Including the following code (with obvious replacements to conform to your own code) should do the trick (dendro-axonic connection): In the target cel...
by Raj
Fri Jul 08, 2005 1:00 pm
Forum: Adding new mechanisms and functions to NEURON
Topic: Stability of steady state approximation
Replies: 3
Views: 5912

Stability of steady state approximation

Dear Forum, I'm using the mod-file included below in a neuron model, depending on whether I use the steady state activation approximation in the breakpoint or the dynamic activation I get completely different stability properties. If I use the steady state I have to go to dt=0.001 ms for stable nume...