# How to plot Parametric plot from NDsolve solutions? [closed]

So I used NDsolve to find the approximation for y1 and y2, shown below.

a = 1;
b = -1;
delta = 0.22;
f = 0.3;
eqs = { y1'[t] == y2[t],
y2'[t] == -b*y1[t] - delta*y2[t] - a*y1[t]^3 + f*Cos[y3[t]],
y3'[t] == 1,
y1 == 1, y2 == 0, y3 == 0 }
sol = NDSolve[eqs, {y1[t], y2[t]}, {t, 0, 200} ]


ParametricPlot[ {y2[t] /. sol, y1[t] /. sol}, {t, 0, 200} ]

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• See the third example under "Basic Examples" of the docs for NDSolve. – Michael E2 Dec 6 '17 at 4:04

Try

ParametricPlot[{y2[t] /. sol[], y1[t] /. sol[]}, {t, 0, 200}] • Or ParametricPlot[{y2[t], y1[t]} /. sol[], {t, 0, 200}] – Chris K Dec 6 '17 at 1:21

Alternative:

sol = NDSolveValue[eqs, {y2, y1}, {t, 0, 200}];
ListLinePlot[Transpose@Through[sol["ValuesOnGrid"]], AspectRatio -> Automatic] 