Re: storing values generated in a 'for'loop

[Ben Abbott]

On Apr 23, 2008, at 9:23 PM, asha g wrote:

> I have a program in which I am iterating V from -80 to
> 80 to generate values of n. then I have to plot n vs
> V.
>
> I wrote
>
> for iter = -80:10:80
> V= iter;
> [alphan,betan,alphah,betah,alpham,betam]= ratcon(V);
> [n,m,h] =
> gatpara2(alphan,betan,alphah,betah,alpham,betam);
>
> n(iter) = n;
> m(iter)= m;
> h(iter)= h;
> V(iter) = V;
> end
> plot(V,n,'r')
>
> The problem I am having is that the command
> n(iter) = n; generates an error message saying
> subscript indexes must be real positive integers or
> logicals.
> How do I write those statements in order that they
> store all values of n,m,h and V during the iteration?
> I am not sure if you need the function files too to
> help me. If so, can send them.
> Thanks for your help.
> Asha


You confusing scalars with vectors. Try something like the code below.

V = -80:10:80;
n = zeros(size(V));
m = zeros(size(V));
h = zeros(size(V));
for iter = 1:numel(V)
  [alphan,betan,alphah,betah,alpham,betam]= ratcon(V(iter));
  [n(iter),m(iter),h(iter)] =  
gatpara2(alphan,betan,alphah,betah,alpham,betam);
endfor
plot(V,n,'r')

This is a good example to introduce yourself to the difference between  
vectors and scalar, and how individual elements of vectors are  
addressed.

Ben