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trying to write a function to compute different account balances using the compo

ID: 3676737 • Letter: T

Question

trying to write a function to compute different account balances using the compound interest formula in matlab. In this case, it needs to be able to support multiple Interest rates and number of years input. I'm currently using nested for loops, and it works fine for the first set of interest rates, but then it runs only the last number of years calculating for the second and any later values in the interest input array

This is the output I'm getting currently:

What am I missing? How can I make it go back to the first value of n for the second run of I?

trying to write a function to compute different account balances using the compound interest formula in matlab. In this case, it needs to be able to support multiple Interest rates and number of years input. I'm currently using nested for loops, and it works fine for the first set of interest rates, but then it runs only the last number of years calculating for the second and any later values in the interest input array

  function ans =  growth_of_money(P,I,n)        disp(['     P     ','n     ','I    ','Total']);     for I = I        for n = n              disp([P,n,I,compound_interest(P,I,n)]);          end       end    end    function T = compound_interest(P,I,n)    T= P.*((1.+I).^n);    end  

This is the output I'm getting currently:

   P     n     I    Total   2     1     4    10     2     3     4   250           2           3           7        1024  

What am I missing? How can I make it go back to the first value of n for the second run of I?

Explanation / Answer

Fortunately, we can create a function in Matlab for the compound interest formula, like this:

function A = comp_int(P, r, n, t)
A = P*(1 + r/n)^(n*t);

and we can call it from another m-file, script, or from the command window, in this way:

P = 10000;
r = 0.05;
n = 12;
t = 3;

format bank
A = comp_int(P, r, n, t)