Simple mortgage calculator

A simple mortgage calculator that will output the monthly payment, the remaining balance, and so on.

% Computer mortgage payment and the respective interest paid each month
%
% Inputs
% L: size of the loan
% rate: annual rate
% years: length of loan in years
%
% Outputs
% P: monthly payment
% In: list of interests paid over the entire loan period
% Ba: Remaining balane over the entire loan period

% please run mortgage_example for detail
% below is an excerpt.

years=20;
annual_rate=0.04; % 4% annual rate
house_value=150000;
downpayment=0.25; % 25% down

loan_size=house_value*(1-downpayment);

[P,In,Ba]=compute_mortgage(loan_size,annual_rate,years);