function f(n, phi)
  h = Rose(n);
  [x, y] = Get(h);
  axis([-1, 10, -1, 10]);
  for k = 0:fix(100/(phi*10))
    [x1, y1] = Rotate(x, y, -phi*k);
    [x1, y1] = Move(x1, y1, phi*k, 0);
    Set(h, x1, y1);
    pause(0.1);
  end
end

function [h]=Rose(n)
  if mod(n,2)==0
    n=n/2;
  end
  t = linspace(0, 2*pi, 200);
  x = cos(n*t).*cos(t);
  y = cos(n*t).*sin(t);
  h=line(x, y);
end

function [x, y] = Get(h)
  x = get(h, 'xdata');
  y = get(h, 'ydata');
end

function Set(h, x, y)
  set(h, 'xdata', x);
  set(h, 'ydata', y);
end

function [x, y] = Rotate(x, y, phi)
  A = [cos(phi), -sin(phi);sin(phi),cos(phi)];
  xy = [x; y];
  xy = A*xy;
  x = xy(1,:)';
  y = xy(2,:)';
end

function [x, y] = Move(x, y, dx, dy)
    x = x+dx;
    y = y+dy;
end