Question: Phase Portrait

restart; with(DEtools) x1 := diff(x(t), t) = (4-x-4*y)*x; y1 := diff(y(t), t) = (4-4*x-y)*y; phaseportrait([diff(x(t), t) = (4-x-4*y)*x, diff(y(t), t) = (4-4*x-y)*y], [x(t), y(t)], x = -20 .. 20, y = -20 .. 20, t = -2 .. 2, [[x(0) = 0, y(0) = 1]], stepsize = 0.5e-1, scene = [y(t), x(t)], linecolour = sin((1/2)*t*Pi), method = classical[foreuler]) I'm trying to specify the domain for x and y but I receive the following error Error, (in DEtools/phaseportrait) initial conditions must be specified in inits The above works when I get rid of x = -20 .. 20, y = -20 .. 20, What did I do wrong?
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