www.neuron.yale.edu

I was wondering how to do the following:

I have created e.g. 3 synapses called syn1, syn2 and syn3. All are dual exponential synapses.

In a loop I would like to change e.g. tau1 of these 3 synapses to different values, like:

for cnt = 1, 3 {
...
syncnt.tau1 = cnt * 5
...
}

Thus, in this loop I'd like to have the counter refer to the different object names and change their respective tau1. Or how can I construct the name of an object with a counter and change some parameters of this object? Or said differently; how can I concatenate a prefix and a cnt value so that it make a object name. Of course, one could say create the synapse with: objectvar syn[3] instead but lets assume this is not an option.

thanks,

Koen Vervaeke

You have a choice of two different approaches.

You could use an "array" of objrefs.
objref syn[n]
declares a collection of objrefs whose names are syn[0]...syn[n-1]
so you could do
for i = 0,n-1 syn.param = f(i)

Or you could use a List. This takes a bit of planning, but it is far more flexible than using "arrays" of names. For one thing, you never have to remember "magic numbers" like how many different syn[] things you have. You start by creating a List, then every time you create a new instance of your synaptic mechanism, you append it to the list. When it comes time to assign properties to these mechanisms, iterate over each object in synlist like so This takes a bit more typing, but the resulting code is much easier to maintain and is free of magic numbers.

Taking this one step further, a way to really clean up this code would be to start by appending the sections of interest to a SectionList or a List of SectionRefs, then iterate over those to create and attach the synaptic mechanisms.

Hi,

I just got know an alternative method that one actually wants to avoid but it works if necessary.
I wanted to add that when one cannot change the names of these synapses then the loop could look like this:

strdef cmd
for cnt = 1, 3 {
sprint(cmd,"syn%d.tau1 = (%d * 5)",cnt, cnt)
execute(cmd)
}

Almost. The "'for' loop" should start at 0. Remember that in hoc, as in C and many other programming languages, the index of the first item is 0, not 1.