# A04.m - For Loop

% get info from user N = input('Enter number of terms in sum: '); % initialize sum to zero s = 0; % Use a for loop to add numbers from 1 to N for n=1:N s = s + n; end % display result to command window % notice that because the variables N and s are integers, we use the %i % formatting in the fprintf statement fprintf('\n') fprintf('Sum of numbers from 1 to %i = %i \n',N,s)

This simple program calculates the sum of integers from 1 to N using a for loop. First, the user is prompted to enter the number `N`. The variable `s` is going store the sum of the integers. It is initialized to zero. In the `for` looop, a counter variable `n` is initialized to `n=0` and then incremented `n=1, 2, 3, ...` until `n` reaches `N`. Every time the loop is executed, the integer `n` is added to the running sum `s`. Once `n` reaches `N` the loop terminates and the variable `s` will contain the sum of the integers 1 + 2 + 3 + ... + (n-1) + n. The final result is displayed to the screen.