function [t, Y] = euleroesplicito(f, a, b, y0, N);
h = (b-a) / N;
% t = linspace(a, b, N+1);
t = zeros(1, N+1);

m = length(y0);
Y = zeros(m, N+1);

t(1) = a;
Y(:, 1) = y0;
for n = 1:N
  t(n+1) = t(n) + h;
  Y(:, n+1) = Y(:, n) + h*f(t(n), Y(:,n));
end