How do I put this formula int matlab?

z=imread('C:\Users\*****\Desktop\Matlab\Homework 3-02 03 04 05\Fig308a.jpg');
for i=1:255
    y(i)=sum(z(:) == i);
end
n=488*373;
for j=1:255
    s(j)=symsum(y(k)/n, k, 1, j);   %% Talking about this part.
end

bar(y), figure, imhist(z), figure, bar(s)

Long story short, what I want to get is such that:

s(1)=y(1)/n

s(2)=y(1)/n+y(2)/n

...

I get the error saying:

"Invalid indexing or function definition. Indexing must follow MATLAB indexing. Function arguments

must be symbolic variables, and function body must be sym expression."

Originial formula.

What should i use?

[madhan ravi]

I am not able to interpret your formula but if the concept is this

s(1)=y(1)/n

s(2)=y(1)/n+y(2)/n

... then why not

cumsum(y/n) % ?

[comment moved to answer section]

[Arda Nova]

Exactly what I am searching for. I tried to search summation types on matlab but couldn't come to this title. Thank you very much.

Answer 1

[madhan ravi]

https://in.mathworks.com/matlabcentral/answers/451685-how-do-i-put-this-formula-int-matlab#comment_684284