??? Subscript indices must either be real positive integers or logicals.

Here's my code:

N = 10;n=0:N;
f(n) = cumsum(((-1).^n)/(3.^n));
g(n) = 3/4+1/4*(-1/3).^n;

I am new to Matlab. Please send a complete solution. Thank you.

[Star Strider]

I will not send a complete solution, but I will point out that MATLAB interprets your f(n) and g(n) statements as array references, not functions. To create functions, see the documentation on Anonymous Functions.

[Matt Fig]

How could we send a complete solution when we don't even have a complete question?

Please learn to format your code. Highlight the code, then push the button that looks like {}Code.

Answer 1

[Muruganandham Subramanian]

Hi, I matalab, you cannot find f(0). so you should start with n=1:N and check the below coding, it may help you..

N = 10;

for n=1:N;

f(n) = cumsum(((-1).^n)/(3.^n));

g(n) = 3/4+1/4*(-1/3).^n;

end

Answer 2

[Andrei Bobrov]

f1 = @(n)cumsum((-1).^n./3.^n);
g1 = @(n)3/4+1/4*(-1/3).^n;

>> N = 10;
>> n1 = 0:N;
>> f1(n1)
ans =
            1      0.66667      0.77778      0.74074      0.75309      0.74897      0.75034      0.74989      0.75004      0.74999         0.75
0:N
ans =
            1      0.66667      0.77778      0.74074      0.75309      0.74897      0.75034      0.74989      0.75004      0.74999         0.75

or

f2 = @(N)cumsum((-1).^(0:N)./3.^(0:N));
g2 = @(N)3/4+1/4*(-1/3).^(0:N);

>> f2(10)
ans =
            1      0.66667      0.77778      0.74074      0.75309      0.74897      0.75034      0.74989      0.75004      0.74999         0.75
>> g2(10)
ans =
            1      0.66667      0.77778      0.74074      0.75309      0.74897      0.75034      0.74989      0.75004      0.74999         0.75