# Animation stays blank during animation

In attempting to answer this question about animating a rolling disk, I constructed a ParametricPlot to Animate. The plot looks fine when not animated, yet while the animation runs the slider moves but there is no plot until the animation stops; after a short delay, the final state of the plot shows up.

How do I ensure the animation shows the elements of the plot?

 mypara[α_] := ParametricPlot[
{
{Cos[θ], Sin[θ]},
{2 Cos[α] + Cos[θ],
2 Sin[α] + Sin[θ]}
},
{θ, 0, 2 π},
{r, 1, 2},
PlotRange -> 3,
Frame -> False
]
Animate[
mypara[α],
{α, 0, 2 π, π/6},
AnimationRepetitions -> 1
] • Use Block[{\$PerformanceGoal}, mypara[\[Alpha]]] p.s. there is y0 definition missing. – Kuba Apr 29 '15 at 8:11
• Thanks @kuba - this solves the immediate problem: the plot is visible. Unfortunately, it doesn't run smoothly but instead jumps to discrete points in the animation. – TransferOrbit Apr 30 '15 at 9:55

## 1 Answer

Another way is just to render the frames first and then use ListAnimate, (BTW I set y0 to -0.1, since its definition is missing)

mypara[\[Alpha]_] :=
ParametricPlot[{{Cos[\[Theta]], Sin[\[Theta]]},
{2 Cos[\[Alpha]] + Cos[\[Theta]], 2 Sin[\[Alpha]] + Sin[\[Theta]]},
{r, 0}},
{\[Theta], 0, 2 \[Pi]}, {r, 1, 2}, PlotRange -> 3, Frame -> False]

list1 = Table[mypara[\[Alpha]], {\[Alpha], 0, 2 \[Pi], \[Pi]/6}]
ListAnimate[list1, AnimationRepetitions -> 1]

• Thank you @lalmei ; this did work once. Unfortunately, the statement Table[myparaL[α], {α, 0, 2 π, π/16}] now crashes my kernel every time if I try it with a higher number of snapshots in the Table, even after restarting Mathematica. – TransferOrbit Apr 30 '15 at 11:11
• @zentient Most likely is due to the fact you are using Pi instead of its numerical value, change the integers to real values 2 ->2.0 16->16.0 etc. – lalmei Apr 30 '15 at 11:52
• Thanks again. Using real values does help slightly. Unfortunately, generating the Table of ParametricPlots crashes regularly when generating only a slightly larger number of plots in the Table. – TransferOrbit May 1 '15 at 8:54