How can I use a for loop to find the summation of a set variable and set number of terms

So I was given the task of creating a UDF that has to do the following:(1) accepts input values for a variable, x, and a set number of terms N.(2) calculate the value of f(x) using N terms and (3) return output value of f(x). Here is what I have so far:

x = input('variable x'); 
n = input('number of terms, n');
for N = (0:n)
  y = sum(x.^N)
end

When I enter in x=2 and n=6 for example, I know the answer is supposed to be 127. But I am not getting the answers summed up, but separate instead. How do I fix this? Thanks.

Answer 1

[Walter Roberson]

total = 0;
...
total = total + y;

[macabe banchero]

That did it. I tried that earlier but my mistake was having it after "end" instead of before. Thanks again!