Re: [Genesis-sim-users] GENESIS advice

[Hugo C. <hug...@gm...>]

Hi Svetlana,

To add randomization to the maximal conductance of a tabchannel, you can
use the setrandfield command after the .p file has been read.

This command can be used to randomize other fields to, or to randomize
fields at each simulation step.

Copying from the Genesis reference manual, at http://genesis-sim.org/GENESIS
/Hyperdoc/Manual-25.html#ss25.146

25.154 setrandfield

Routine Name:   setrandfield

Description:    Sets an element field to a random value

Usage:                                  | [-uniform low high]
                setrandfield path field | [-gaussian mean sd]
                                        | [-exponential mid max]

Example:        setrandfield /pyr/pyramidal[]/HH_Na_channel \
                    X_alpha_V0 -gaussian -40 3

Notes:          In the example above (from Scripts/piriform/pyramidal.g),
                setrandfield is being used to give some variation to the
                voltage dependence of the activation of Na channels used in
                all of the pyramidal cells used in the model.  In this case,
                there is a gaussian distribution about the mean of -40 mV,
                with a standard deviation of 3 mV.  Another use of the
                setrandfield comamnd would be to use it in script function to
                be executed as the command of a script_out object, or as the
                PROCESS action of an extended object, in order to randomly
                change a field at every time step.  This would be a way to
                inject a noise current into a compartment, for example.

                The -uniform option gives a a random number taken from a
                uniform distribution in the range "low" to "high".

                The -exponential option gives a random number taken from an
                exponential distribution with a minimum value of zero, a 1/e
                point of "mid" and a maximum value of "max".  Versions of
                GENESIS prior to 2.2 used a different interpretation of the
                two arguments.

See also: setfield
<http://genesis-sim.org/GENESIS/Hyperdoc/Manual-25.html#setfield>

I hope this helps.


Hugo



On Fri, Sep 21, 2018 at 2:23 PM, Gladycheva, Svetlana <
sgl...@to...> wrote:

> Hello colleagues -
>
>
> any wisdom of how to add randomization to tabchannel maximum conductance?
>
> cell.p file where max conductance parameter is read from, for example:
>
>
> soma none 0 0 15 16 KA1  300
>
> doesn't seem to allow to replace the number (300) with an expression
> ({rand 200 400} ) or with a variable..
>
> Thanks...
> Svetlana
>
>
>
>
> _______________________________________________
> Genesis-sim-users mailing list
> Gen...@li...
> https://lists.sourceforge.net/lists/listinfo/genesis-sim-users
>
>


-- 
Hugo



--

                  Hugo Cornelis, Ph.D.

                    Agora Classica -- CTO
              http://www.agoraclassica.com/

            GENESIS-3 -- lead architect
              http://www.genesis-sim.org/