Summation expression for loop

I have to write a "For loop" for the expression below and that what I wrote. But I am not sure if it is write or not. If someone would verify my work, I would appreciate it. Thank you in advance.

sum1 = 0;
for ii = 1:2:9;
sum2 = 0;
for jj = 2:2:10;
sum2+cos(ii.*jj.*pi./'12);
end
sum1 = sum1+(sum2.*ii);
end

Answer 1

[Walter Roberson]

syms I J
symsum(symsum(cos((2*I-1)*(2*J)*sym('pi')/12), J, 1, 5), I, 1, 5)
%result is 0

I used I and J instead of i and j because symsum() needs consecutive values not values incrementing by 2

[Birdman]

Firstly I used symsum but when I noticed what you said I decided not to use it.

Answer 2

[Birdman]

Well, I believe your nested for loop structure is wrong for your problem since it does require two separate for loops. I tried to show the solution in symbolic and for loop way. Please see the following approaches:

%symbolic way
syms i j
fun1=cos((i.*j.*pi)./12);
jj=subs(j,2:2:10);
fun2=sum(subs(fun1,j,jj))
ii=subs(i,1:2:9);
result=sum(subs(i.*fun2,i,ii))
%%result is zero.

%for loop
syms i j
sumj=0;
sumi=0;
for j=2:2:10
    sumj=sumj+cos((i.*j.*pi)/12);
end
for i=1:2:9
    sumi=sumi+i*subs(sumj,i);
end
%%sumi is zero.