Euler Method Tank + Salt

Hello!

clear; close all; clc

%% Parameters

tank1 = 100; % gallons
tank2 = 100; % gallons
tank1salt = 1000; % grams of salt
tank2salt = 100;  % grams of salt 
h = 0.01; % step size


f1 = @(x,y) (5/100)*y - (15/100)*x
f2 = @(x,y) (15/100)*x - (15/100)*y

f = [f1, f2];

function [t,y] = ode_eulerfinal(f, tspan, y0, h)

f = 

t = tspan(1):h:tspan(2);
y = nan(size(t));
y(1) = y0;

for i = 1:length(t)-1
    y(i+1) = y(i) + h * f(t(i), y(i));
end

end