% solucion de la ecuacion de ondas unidimensional
% la cuerda vibrante
clear all
ej1 = 1;

if ej1
  N = 2;
  a = [0 0];%[1 0.2];
  b = [0.5 0];
else
  N = 5;
  a = [1 0.2 0 0 0.1];
  b = [0 0 0 0 0];
end

n = [1:N];
x = [0:.01:1];

npix = pi*n' * x;

senox = sin(npix);

for t=0:.01:4
  u = (a.*cos(n*pi*t) + b.*sin(n*pi*t)) * senox;
  plot(x,u);
  axis([0 1 -2 2])
  if (t==0)
    pause
  else
    pause(0.02)
  end
end

pause
for t=0:.01:4
  u1 = (a(1).*cos(1*pi*t)) * senox(1,:);
  if (ej1)
      u2 = (a(2).*cos(2*pi*t)) * senox(2,:);
      u  = u1 + u2;
      plot(x,u,x,u1,x,u2);
  else
      u2 = (a(2).*cos(2*pi*t)) * senox(2,:);
      u5 = (a(5).*cos(5*pi*t)) * senox(5,:);
      u  = u1 + u2 + u5;
  plot(x,u,x,u1,x,u2,x,u5);

  end

  axis([0 1 -2 2])
  if (t==0)
    pause
  else
    pause(0.05)
  end
end