# Poincare Plotting

I'm trying to perform a List Plot, but I'm having an issue trying to plot the two given functions accordingly. What is the syntax suppose to look like for Sow within the WhenEvent function?

ClearAll["Global*"]
q = 0.2; \[Omega] = 2.44; \[Beta] = 0.03; m = 3.2; \[Kappa] = 2.63; \
\[CapitalOmega] = 2.4;
sol = Reap[NDSolveValue[{
f''[t] + 2 \[Beta] f'[t] + (1 - m \[Omega]^2 u[t]) f[t] == 0,
u''[t] +
2 \[Beta] u[t] + \[Omega]^2 u[
t] + \[Kappa] (f[t]*f''[t] + (f'[t])^2) ==
q/m Cos[\[CapitalOmega] t],
f[0] == 0, f'[0] == 0, u[0] == 0, u'[0] == 0,
WhenEvent[Mod[t, 2 \[Pi]/\[CapitalOmega]] == 0,
Sow[{f[t], f'[t]}, {u[t], u'[t]}]]}
, {f, u}, {t, 0, 30000}, MaxSteps -> Infinity]]
ListPlot[pst, PlotStyle -> PointSize[0.0025], PlotRange -> All]

• What is pst in the ListPlot? Nov 24, 2019 at 22:45
• That was meant to be my list of points, but I changed the variable for the NDSolveValue setup to see what came out of it without problems regarding the list shapes not matching Nov 24, 2019 at 23:14
• Plot[sol[[1, 2]][x], {x, 0, 30000}]`? Nov 24, 2019 at 23:59
• Sadly, that doesn't work :( Dec 1, 2019 at 4:01