error when the input is zero

hi all, i am doing a code on MATLAB while the variable input is :

T= Temperature

G= irradiation

but I am getting an error when I have G value equal to zero. the error is :

??? Attempted to access (0); index must be a positive integer or logical.

my code is :

IL=(ISC+(mi)*(T-T1))*(G/G1);
IO1=ISC/(exp((VOC*q)/(NS*A*k*T1))-1); 
IO=IO1*((T/T1)^3)*exp((q*EG/(A*k))*((1/T1)-(1/T))); 
RS=((NS*A*k*T1/q)*log(((ISC-IM1)/IO1)+1)-VM1)/IM1; 
h=IL/1000; 
I=0:h:IL; 
N=length(I); 
V(N)=0; %Error is here on this line!!
for i=1:(N-1)
V(i)=(NS*A*k*T/q)*log(1+(IL-I(i))/IO)-I(i)*RS; %
end

why I am getting this error and how to overcome it ?? please help and advice. thanks

Answer 1

[Walter Roberson]

When G is 0, then IL comes out 0. Then 0:h:IL is 0 to 0, which has a length (N) of 0. You then attempt to assign to that 0'th element.

What result would you like to get out when the length comes out 0?

Consider using

I = linspace(0, IL, 1001);

instead of the h and I code you hae at the moment.

[Samer Husam]

thanks Mr. Walter, you solution is works... thanks again

Answer 2

[Babak]

If you set G = 0, then IL will be evaluated as 0.

When IL = 0, then h = 0 and I = 0:h:IL which is I = [].

And N = length(I) is 0.

Assignment of V(N) is like V(0) is meaningless.

I recommand you not set G = 0. I don't know the reason why it ccan/should be zero.

[Samer Husam]

Mr babak, the reason to use G = zero cuz the irradiation of the sun is equal to zero in the night.

Mr. walter's answer works very well