I have the code below and there is an error which couldn't catch any help please ?

hyd_dem=A/2.3; % each kg require 2.3kw ((54.6kwh/kg))
Ele_consum=B/2.3; %2.3kw/kg  ((54.6kwh/kg))
Num_ele=Ele_consum/1500; % 1500 kg/day is rated electrolyser production 
Num_ele = round( Num_ele,0); % convert the decimal numbers to integers
hydrogen_excess= Ele_consum-hyd_dem; % excess and deficiency of hydrogen
hydrogen_extra= hyd_dem-Ele_consum;
H2 =max(hydrogen_excess);  
F=[0 0];
i=0;
while(i<=365)
  i=i+1;
  if(hydrogen_excess(i)>=0)
    if (F(i)<=H2)
      hydrogen_excess(i)=hydrogen_excess(i);
    else
      hydrogen_excess(i)=0;
    end
  else
    Excess(i)=0;
  end
end       % [EDITED, Jan, ???]

if(hydrogen_extra(i)>=0)
  if (F(i)>=hydrogen_extra(i))
    hydrogen_extra(i)=hydrogen_extra(i);
  else
    hydrogen_extra(i)=F(i);
  end

    if(hydrogen_excess(i)>0)
      F(i+1)=F(i)+hydrogen_excess(i);
    elseif(hydrogen_extra(i)>0)
      F(i+1)=F(i)-hydrogen_extra(i);
    else
      F(i+1)=F(i);
    end
  end

%%%% the error was

((Attempted to access F(6); index out of bounds because numel(F)=2.
Error in Untitled4 (line 17)
if (F(i)<=H2)  ))

Answer 1

[Image Analyst]

Somehow i is getting up to 6, but you only defined F as having 2 values, both zero. Make F have at least as many values as the value that you expect i to reach.

[ABDULLA RAHIL]

I cant guess the F value since its change between the excess and extra so difficult to if u put any other values still the same error

Answer 2

[Jan]

I've edited the code in the your question and added a standard indentation. Then it gets obvious, that the loop runs without updating F. I assume, that the end marked by [???] is misplaced and should be moved to the end of the code.

Use the auto-indentation to see such problems immediately. Or mark the code in the editor and hit Ctrl-i.

But even if this is the problem, the error message would occur at i==3 already. The message for F(6) is impossible with the shown code. So please post the code, which causes the error to avoid yo confuse the readers.